      1 'use strict';
      2
      3 /**
      4  * @license
      5  * Copyright 2006 Dan Vanderkam (danvdk@gmail.com)
      6  * MIT-licenced: https://opensource.org/license/MIT
      7  */
      8
      9 /**
     10  * @fileoverview Creates an interactive, zoomable graph based on a CSV file or
     11  * string. Dygraph can handle multiple series with or without high/low bands.
     12  * The date/value ranges will be automatically set. Dygraph uses the
     13  * <canvas> tag, so it only works in FF1.5+.
     14  * See the source or https://dygraphs.com/ for more information.
     15  * @author danvdk@gmail.com (Dan Vanderkam)
     16  */
     17
     18 /*
     19   Usage:
     20    <div id="graphdiv" style="width:800px; height:500px;"></div>
     21    <script type="text/javascript"><!--//--><![CDATA[//><!--
     22    $(function onDOMready() {
     23      new Dygraph(document.getElementById("graphdiv"),
     24                  "datafile.csv",  // CSV file with headers
     25                  { }); // options
     26    });
     27    //--><!]]></script>
     28
     29  The CSV file is of the form
     30
     31    Date,SeriesA,SeriesB,SeriesC
     32    YYYY-MM-DD,A1,B1,C1
     33    YYYY-MM-DD,A2,B2,C2
     34
     35  If the 'errorBars' option is set in the constructor, the input should be of
     36  the form
     37    Date,SeriesA,SeriesB,...
     38    YYYY-MM-DD,A1,sigmaA1,B1,sigmaB1,...
     39    YYYY-MM-DD,A2,sigmaA2,B2,sigmaB2,...
     40
     41  If the 'fractions' option is set, the input should be of the form:
     42
     43    Date,SeriesA,SeriesB,...
     44    YYYY-MM-DD,A1/B1,A2/B2,...
     45    YYYY-MM-DD,A1/B1,A2/B2,...
     46
     47  And high/low bands will be calculated automatically using a binomial distribution.
     48
     49  For further documentation and examples, see https://dygraphs.com/
     50  */
     51
     52 import DygraphLayout from './dygraph-layout';
     53 import DygraphCanvasRenderer from './dygraph-canvas';
     54 import DygraphOptions from './dygraph-options';
     55 import DygraphInteraction from './dygraph-interaction-model';
     56 import * as DygraphTickers from './dygraph-tickers';
     57 import * as utils from './dygraph-utils';
     58 import DEFAULT_ATTRS from './dygraph-default-attrs';
     59 import OPTIONS_REFERENCE from './dygraph-options-reference';
     60 import IFrameTarp from './iframe-tarp';
     61
     62 import DefaultHandler from './datahandler/default';
     63 import ErrorBarsHandler from './datahandler/bars-error';
     64 import CustomBarsHandler from './datahandler/bars-custom';
     65 import DefaultFractionHandler from './datahandler/default-fractions';
     66 import FractionsBarsHandler from './datahandler/bars-fractions';
     67 import BarsHandler from './datahandler/bars';
     68
     69 import AnnotationsPlugin from './plugins/annotations';
     70 import AxesPlugin from './plugins/axes';
     71 import ChartLabelsPlugin from './plugins/chart-labels';
     72 import GridPlugin from './plugins/grid';
     73 import LegendPlugin from './plugins/legend';
     74 import RangeSelectorPlugin from './plugins/range-selector';
     75
     76 import GVizChart from './dygraph-gviz';
     77
     78 /**
     79  * @class Creates an interactive, zoomable chart.
     80  * @name Dygraph
     81  *
     82  * @constructor
     83  * @param {div | String} div A div or the id of a div into which to construct
     84  * the chart. Must not have any padding.
     85  * @param {String | Function} file A file containing CSV data or a function
     86  * that returns this data. The most basic expected format for each line is:
     87  * "YYYY/MM/DD,val1,val2,..."
     88  * For more information, see: https://dygraphs.com/data.html
     89  *
     90  * @param {Object} attrs Various other attributes, e.g. errorBars determines
     91  * whether the input data contains error ranges. For a complete list of
     92  * options, see: https://dygraphs.com/options.html
     93  */
     94 var Dygraph = function Dygraph(div, data, opts) {
     95   this.__init__(div, data, opts);
     96 };
     97
     98 Dygraph.NAME = "Dygraph";
     99 Dygraph.VERSION = "2.2.2";
    100
    101 // internal autoloader workaround
    102 var _addrequire = {};
    103 Dygraph._require = function require(what) {
    104   return (what in _addrequire ? _addrequire[what] : Dygraph._require._b(what));
    105 };
    106 Dygraph._require._b = null; // set by xfrmmodmap-dy.js
    107 Dygraph._require.add = function add(what, towhat) {
    108   _addrequire[what] = towhat;
    109 };
    110
    111 // Various default values
    112 Dygraph.DEFAULT_ROLL_PERIOD = 1;
    113 Dygraph.DEFAULT_WIDTH = 480;
    114 Dygraph.DEFAULT_HEIGHT = 320;
    115
    116 // For max 60 Hz. animation:
    117 Dygraph.ANIMATION_STEPS = 12;
    118 Dygraph.ANIMATION_DURATION = 200;
    119
    120 /**
    121  * Standard plotters. These may be used by clients.
    122  * Available plotters are:
    123  * - Dygraph.Plotters.linePlotter: draws central lines (most common)
    124  * - Dygraph.Plotters.errorPlotter: draws high/low bands
    125  * - Dygraph.Plotters.fillPlotter: draws fills under lines (used with fillGraph)
    126  *
    127  * By default, the plotter is [fillPlotter, errorPlotter, linePlotter].
    128  * This causes all the lines to be drawn over all the fills/bands.
    129  */
    130 Dygraph.Plotters = DygraphCanvasRenderer._Plotters;
    131
    132 // Used for initializing annotation CSS rules only once.
    133 Dygraph.addedAnnotationCSS = false;
    134
    135 /**
    136  * Initializes the Dygraph. This creates a new DIV and constructs the PlotKit
    137  * and context <canvas> inside of it. See the constructor for details.
    138  * on the parameters.
    139  * @param {Element} div the Element to render the graph into.
    140  * @param {string | Function} file Source data
    141  * @param {Object} attrs Miscellaneous other options
    142  * @private
    143  */
    144 Dygraph.prototype.__init__ = function(div, file, attrs) {
    145   this.is_initial_draw_ = true;
    146   this.readyFns_ = [];
    147
    148   // Support two-argument constructor
    149   if (attrs === null || attrs === undefined) { attrs = {}; }
    150
    151   attrs = Dygraph.copyUserAttrs_(attrs);
    152
    153   if (typeof(div) == 'string') {
    154     div = document.getElementById(div);
    155   }
    156
    157   if (!div) {
    158     throw new Error('Constructing dygraph with a non-existent div!');
    159   }
    160
    161   // Copy the important bits into the object
    162   // TODO(danvk): most of these should just stay in the attrs_ dictionary.
    163   this.maindiv_ = div;
    164   this.file_ = file;
    165   this.rollPeriod_ = attrs.rollPeriod || Dygraph.DEFAULT_ROLL_PERIOD;
    166   this.previousVerticalX_ = -1;
    167   this.fractions_ = attrs.fractions || false;
    168   this.dateWindow_ = attrs.dateWindow || null;
    169
    170   this.annotations_ = [];
    171
    172   // Clear the div. This ensure that, if multiple dygraphs are passed the same
    173   // div, then only one will be drawn.
    174   div.innerHTML = "";
    175
    176   const resolved = window.getComputedStyle(div, null);
    177   if (resolved.paddingLeft !== "0px" ||
    178       resolved.paddingRight !== "0px" ||
    179       resolved.paddingTop !== "0px" ||
    180       resolved.paddingBottom !== "0px")
    181     console.error('Main div contains padding; graph will misbehave');
    182
    183   // For historical reasons, the 'width' and 'height' options trump all CSS
    184   // rules _except_ for an explicit 'width' or 'height' on the div.
    185   // As an added convenience, if the div has zero height (like <div></div> does
    186   // without any styles), then we use a default height/width.
    187   if (div.style.width === '' && attrs.width) {
    188     div.style.width = attrs.width + "px";
    189   }
    190   if (div.style.height === '' && attrs.height) {
    191     div.style.height = attrs.height + "px";
    192   }
    193   if (div.style.height === '' && div.clientHeight === 0) {
    194     div.style.height = Dygraph.DEFAULT_HEIGHT + "px";
    195     if (div.style.width === '') {
    196       div.style.width = Dygraph.DEFAULT_WIDTH + "px";
    197     }
    198   }
    199   // These will be zero if the dygraph's div is hidden. In that case,
    200   // use the user-specified attributes if present. If not, use zero
    201   // and assume the user will call resize to fix things later.
    202   this.width_ = div.clientWidth || attrs.width || 0;
    203   this.height_ = div.clientHeight || attrs.height || 0;
    204
    205   // TODO(danvk): set fillGraph to be part of attrs_ here, not user_attrs_.
    206   if (attrs.stackedGraph) {
    207     attrs.fillGraph = true;
    208     // TODO(nikhilk): Add any other stackedGraph checks here.
    209   }
    210
    211   // DEPRECATION WARNING: All option processing should be moved from
    212   // attrs_ and user_attrs_ to options_, which holds all this information.
    213   //
    214   // Dygraphs has many options, some of which interact with one another.
    215   // To keep track of everything, we maintain two sets of options:
    216   //
    217   //  this.user_attrs_   only options explicitly set by the user.
    218   //  this.attrs_        defaults, options derived from user_attrs_, data.
    219   //
    220   // Options are then accessed this.attr_('attr'), which first looks at
    221   // user_attrs_ and then computed attrs_. This way Dygraphs can set intelligent
    222   // defaults without overriding behavior that the user specifically asks for.
    223   this.user_attrs_ = {};
    224   utils.update(this.user_attrs_, attrs);
    225
    226   // This sequence ensures that Dygraph.DEFAULT_ATTRS is never modified.
    227   this.attrs_ = {};
    228   utils.updateDeep(this.attrs_, DEFAULT_ATTRS);
    229
    230   this.boundaryIds_ = [];
    231   this.setIndexByName_ = {};
    232   this.datasetIndex_ = [];
    233
    234   this.registeredEvents_ = [];
    235   this.eventListeners_ = {};
    236
    237   this.attributes_ = new DygraphOptions(this);
    238
    239   // Create the containing DIV and other interactive elements
    240   this.createInterface_();
    241
    242   // Activate plugins.
    243   this.plugins_ = [];
    244   var plugins = Dygraph.PLUGINS.concat(this.getOption('plugins'));
    245   for (var i = 0; i < plugins.length; i++) {
    246     // the plugins option may contain either plugin classes or instances.
    247     // Plugin instances contain an activate method.
    248     var Plugin = plugins[i];  // either a constructor or an instance.
    249     var pluginInstance;
    250     if (typeof(Plugin.activate) !== 'undefined') {
    251       pluginInstance = Plugin;
    252     } else {
    253       pluginInstance = new Plugin();
    254     }
    255
    256     var pluginDict = {
    257       plugin: pluginInstance,
    258       events: {},
    259       options: {},
    260       pluginOptions: {}
    261     };
    262
    263     var handlers = pluginInstance.activate(this);
    264     for (var eventName in handlers) {
    265       if (!handlers.hasOwnProperty(eventName)) continue;
    266       // TODO(danvk): validate eventName.
    267       pluginDict.events[eventName] = handlers[eventName];
    268     }
    269
    270     this.plugins_.push(pluginDict);
    271   }
    272
    273   // At this point, plugins can no longer register event handlers.
    274   // Construct a map from event -> ordered list of [callback, plugin].
    275   for (var i = 0; i < this.plugins_.length; i++) {
    276     var plugin_dict = this.plugins_[i];
    277     for (var eventName in plugin_dict.events) {
    278       if (!plugin_dict.events.hasOwnProperty(eventName)) continue;
    279       var callback = plugin_dict.events[eventName];
    280
    281       var pair = [plugin_dict.plugin, callback];
    282       if (!(eventName in this.eventListeners_)) {
    283         this.eventListeners_[eventName] = [pair];
    284       } else {
    285         this.eventListeners_[eventName].push(pair);
    286       }
    287     }
    288   }
    289
    290   this.createDragInterface_();
    291
    292   this.start_();
    293 };
    294
    295 /**
    296  * Triggers a cascade of events to the various plugins which are interested in them.
    297  * Returns true if the "default behavior" should be prevented, i.e. if one
    298  * of the event listeners called event.preventDefault().
    299  * @private
    300  */
    301 Dygraph.prototype.cascadeEvents_ = function(name, extra_props) {
    302   if (!(name in this.eventListeners_)) return false;
    303
    304   // QUESTION: can we use objects & prototypes to speed this up?
    305   var e = {
    306     dygraph: this,
    307     cancelable: false,
    308     defaultPrevented: false,
    309     preventDefault: function() {
    310       if (!e.cancelable) throw "Cannot call preventDefault on non-cancelable event.";
    311       e.defaultPrevented = true;
    312     },
    313     propagationStopped: false,
    314     stopPropagation: function() {
    315       e.propagationStopped = true;
    316     }
    317   };
    318   utils.update(e, extra_props);
    319
    320   var callback_plugin_pairs = this.eventListeners_[name];
    321   if (callback_plugin_pairs) {
    322     for (var i = callback_plugin_pairs.length - 1; i >= 0; i--) {
    323       var plugin = callback_plugin_pairs[i][0];
    324       var callback = callback_plugin_pairs[i][1];
    325       callback.call(plugin, e);
    326       if (e.propagationStopped) break;
    327     }
    328   }
    329   return e.defaultPrevented;
    330 };
    331
    332 /**
    333  * Fetch a plugin instance of a particular class. Only for testing.
    334  * @private
    335  * @param {!Class} type The type of the plugin.
    336  * @return {Object} Instance of the plugin, or null if there is none.
    337  */
    338 Dygraph.prototype.getPluginInstance_ = function(type) {
    339   for (var i = 0; i < this.plugins_.length; i++) {
    340     var p = this.plugins_[i];
    341     if (p.plugin instanceof type) {
    342       return p.plugin;
    343     }
    344   }
    345   return null;
    346 };
    347
    348 /**
    349  * Returns the zoomed status of the chart for one or both axes.
    350  *
    351  * Axis is an optional parameter. Can be set to 'x' or 'y'.
    352  *
    353  * The zoomed status for an axis is set whenever a user zooms using the mouse
    354  * or when the dateWindow or valueRange are updated. Double-clicking or calling
    355  * resetZoom() resets the zoom status for the chart.
    356  */
    357 Dygraph.prototype.isZoomed = function(axis) {
    358   const isZoomedX = !!this.dateWindow_;
    359   if (axis === 'x') return isZoomedX;
    360
    361   const isZoomedY = this.axes_.map(axis => !!axis.valueRange).indexOf(true) >= 0;
    362   if (axis === null || axis === undefined) {
    363     return isZoomedX || isZoomedY;
    364   }
    365   if (axis === 'y') return isZoomedY;
    366
    367   throw new Error(`axis parameter is [${axis}] must be null, 'x' or 'y'.`);
    368 };
    369
    370 /**
    371  * Returns information about the Dygraph object, including its containing ID.
    372  */
    373 Dygraph.prototype.toString = function() {
    374   var maindiv = this.maindiv_;
    375   var id = (maindiv && maindiv.id) ? maindiv.id : maindiv;
    376   return "[Dygraph " + id + "]";
    377 };
    378
    379 /**
    380  * @private
    381  * Returns the value of an option. This may be set by the user (either in the
    382  * constructor or by calling updateOptions) or by dygraphs, and may be set to a
    383  * per-series value.
    384  * @param {string} name The name of the option, e.g. 'rollPeriod'.
    385  * @param {string} [seriesName] The name of the series to which the option
    386  * will be applied. If no per-series value of this option is available, then
    387  * the global value is returned. This is optional.
    388  * @return {...} The value of the option.
    389  */
    390 Dygraph.prototype.attr_ = function(name, seriesName) {
    391   if (typeof process !== 'undefined' && process.env.NODE_ENV != 'production') {
    392     // For "production" code, this gets removed by uglifyjs.
    393     if (typeof(OPTIONS_REFERENCE) === 'undefined') {
    394       console.error('Must include options reference JS for testing');
    395     } else if (!OPTIONS_REFERENCE.hasOwnProperty(name)) {
    396       console.error('Dygraphs is using property ' + name + ', which has no ' +
    397                     'entry in the Dygraphs.OPTIONS_REFERENCE listing.');
    398       // Only log this error once.
    399       OPTIONS_REFERENCE[name] = true;
    400     }
    401   }
    402   return seriesName ? this.attributes_.getForSeries(name, seriesName) : this.attributes_.get(name);
    403 };
    404
    405 /**
    406  * Returns the current value for an option, as set in the constructor or via
    407  * updateOptions. You may pass in an (optional) series name to get per-series
    408  * values for the option.
    409  *
    410  * All values returned by this method should be considered immutable. If you
    411  * modify them, there is no guarantee that the changes will be honored or that
    412  * dygraphs will remain in a consistent state. If you want to modify an option,
    413  * use updateOptions() instead.
    414  *
    415  * @param {string} name The name of the option (e.g. 'strokeWidth')
    416  * @param {string=} opt_seriesName Series name to get per-series values.
    417  * @return {*} The value of the option.
    418  */
    419 Dygraph.prototype.getOption = function(name, opt_seriesName) {
    420   return this.attr_(name, opt_seriesName);
    421 };
    422
    423 /**
    424  * Like getOption(), but specifically returns a number.
    425  * This is a convenience function for working with the Closure Compiler.
    426  * @param {string} name The name of the option (e.g. 'strokeWidth')
    427  * @param {string=} opt_seriesName Series name to get per-series values.
    428  * @return {number} The value of the option.
    429  * @private
    430  */
    431 Dygraph.prototype.getNumericOption = function(name, opt_seriesName) {
    432   return /** @type{number} */(this.getOption(name, opt_seriesName));
    433 };
    434
    435 /**
    436  * Like getOption(), but specifically returns a string.
    437  * This is a convenience function for working with the Closure Compiler.
    438  * @param {string} name The name of the option (e.g. 'strokeWidth')
    439  * @param {string=} opt_seriesName Series name to get per-series values.
    440  * @return {string} The value of the option.
    441  * @private
    442  */
    443 Dygraph.prototype.getStringOption = function(name, opt_seriesName) {
    444   return /** @type{string} */(this.getOption(name, opt_seriesName));
    445 };
    446
    447 /**
    448  * Like getOption(), but specifically returns a boolean.
    449  * This is a convenience function for working with the Closure Compiler.
    450  * @param {string} name The name of the option (e.g. 'strokeWidth')
    451  * @param {string=} opt_seriesName Series name to get per-series values.
    452  * @return {boolean} The value of the option.
    453  * @private
    454  */
    455 Dygraph.prototype.getBooleanOption = function(name, opt_seriesName) {
    456   return /** @type{boolean} */(this.getOption(name, opt_seriesName));
    457 };
    458
    459 /**
    460  * Like getOption(), but specifically returns a function.
    461  * This is a convenience function for working with the Closure Compiler.
    462  * @param {string} name The name of the option (e.g. 'strokeWidth')
    463  * @param {string=} opt_seriesName Series name to get per-series values.
    464  * @return {function(...)} The value of the option.
    465  * @private
    466  */
    467 Dygraph.prototype.getFunctionOption = function(name, opt_seriesName) {
    468   return /** @type{function(...)} */(this.getOption(name, opt_seriesName));
    469 };
    470
    471 Dygraph.prototype.getOptionForAxis = function(name, axis) {
    472   return this.attributes_.getForAxis(name, axis);
    473 };
    474
    475 /**
    476  * @private
    477  * @param {string} axis The name of the axis (i.e. 'x', 'y' or 'y2')
    478  * @return {...} A function mapping string -> option value
    479  */
    480 Dygraph.prototype.optionsViewForAxis_ = function(axis) {
    481   var self = this;
    482   return function(opt) {
    483     var axis_opts = self.user_attrs_.axes;
    484     if (axis_opts && axis_opts[axis] && axis_opts[axis].hasOwnProperty(opt)) {
    485       return axis_opts[axis][opt];
    486     }
    487
    488     // I don't like that this is in a second spot.
    489     if (axis === 'x' && opt === 'logscale') {
    490       // return the default value.
    491       // TODO(konigsberg): pull the default from a global default.
    492       return false;
    493     }
    494
    495     // user-specified attributes always trump defaults, even if they're less
    496     // specific.
    497     if (typeof(self.user_attrs_[opt]) != 'undefined') {
    498       return self.user_attrs_[opt];
    499     }
    500
    501     axis_opts = self.attrs_.axes;
    502     if (axis_opts && axis_opts[axis] && axis_opts[axis].hasOwnProperty(opt)) {
    503       return axis_opts[axis][opt];
    504     }
    505     // check old-style axis options
    506     // TODO(danvk): add a deprecation warning if either of these match.
    507     if (axis == 'y' && self.axes_[0].hasOwnProperty(opt)) {
    508       return self.axes_[0][opt];
    509     } else if (axis == 'y2' && self.axes_[1].hasOwnProperty(opt)) {
    510       return self.axes_[1][opt];
    511     }
    512     return self.attr_(opt);
    513   };
    514 };
    515
    516 /**
    517  * Returns the current rolling period, as set by the user or an option.
    518  * @return {number} The number of points in the rolling window
    519  */
    520 Dygraph.prototype.rollPeriod = function() {
    521   return this.rollPeriod_;
    522 };
    523
    524 /**
    525  * Returns the currently-visible x-range. This can be affected by zooming,
    526  * panning or a call to updateOptions.
    527  * Returns a two-element array: [left, right].
    528  * If the Dygraph has dates on the x-axis, these will be millis since epoch.
    529  */
    530 Dygraph.prototype.xAxisRange = function() {
    531   return this.dateWindow_ ? this.dateWindow_ : this.xAxisExtremes();
    532 };
    533
    534 /**
    535  * Returns the lower- and upper-bound x-axis values of the data set.
    536  */
    537 Dygraph.prototype.xAxisExtremes = function() {
    538   var pad = this.getNumericOption('xRangePad') / this.plotter_.area.w;
    539   if (this.numRows() === 0) {
    540     return [0 - pad, 1 + pad];
    541   }
    542   var left = this.rawData_[0][0];
    543   var right = this.rawData_[this.rawData_.length - 1][0];
    544   if (pad) {
    545     // Must keep this in sync with dygraph-layout _evaluateLimits()
    546     var range = right - left;
    547     left -= range * pad;
    548     right += range * pad;
    549   }
    550   return [left, right];
    551 };
    552
    553 /**
    554  * Returns the lower- and upper-bound y-axis values for each axis. These are
    555  * the ranges you'll get if you double-click to zoom out or call resetZoom().
    556  * The return value is an array of [low, high] tuples, one for each y-axis.
    557  */
    558 Dygraph.prototype.yAxisExtremes = function() {
    559   // TODO(danvk): this is pretty inefficient
    560   const packed = this.gatherDatasets_(this.rolledSeries_, null);
    561   const { extremes } = packed;
    562   const saveAxes = this.axes_;
    563   this.computeYAxisRanges_(extremes);
    564   const newAxes = this.axes_;
    565   this.axes_ = saveAxes;
    566   return newAxes.map(axis => axis.extremeRange);
    567 }
    568
    569 /**
    570  * Returns the currently-visible y-range for an axis. This can be affected by
    571  * zooming, panning or a call to updateOptions. Axis indices are zero-based. If
    572  * called with no arguments, returns the range of the first axis.
    573  * Returns a two-element array: [bottom, top].
    574  */
    575 Dygraph.prototype.yAxisRange = function(idx) {
    576   if (typeof(idx) == "undefined") idx = 0;
    577   if (idx < 0 || idx >= this.axes_.length) {
    578     return null;
    579   }
    580   var axis = this.axes_[idx];
    581   return [ axis.computedValueRange[0], axis.computedValueRange[1] ];
    582 };
    583
    584 /**
    585  * Returns the currently-visible y-ranges for each axis. This can be affected by
    586  * zooming, panning, calls to updateOptions, etc.
    587  * Returns an array of [bottom, top] pairs, one for each y-axis.
    588  */
    589 Dygraph.prototype.yAxisRanges = function() {
    590   var ret = [];
    591   for (var i = 0; i < this.axes_.length; i++) {
    592     ret.push(this.yAxisRange(i));
    593   }
    594   return ret;
    595 };
    596
    597 // TODO(danvk): use these functions throughout dygraphs.
    598 /**
    599  * Convert from data coordinates to canvas/div X/Y coordinates.
    600  * If specified, do this conversion for the coordinate system of a particular
    601  * axis. Uses the first axis by default.
    602  * Returns a two-element array: [X, Y]
    603  *
    604  * Note: use toDomXCoord instead of toDomCoords(x, null) and use toDomYCoord
    605  * instead of toDomCoords(null, y, axis).
    606  */
    607 Dygraph.prototype.toDomCoords = function(x, y, axis) {
    608   return [ this.toDomXCoord(x), this.toDomYCoord(y, axis) ];
    609 };
    610
    611 /**
    612  * Convert from data x coordinates to canvas/div X coordinate.
    613  * If specified, do this conversion for the coordinate system of a particular
    614  * axis.
    615  * Returns a single value or null if x is null.
    616  */
    617 Dygraph.prototype.toDomXCoord = function(x) {
    618   if (x === null) {
    619     return null;
    620   }
    621
    622   var area = this.plotter_.area;
    623   var xRange = this.xAxisRange();
    624   return area.x + (x - xRange[0]) / (xRange[1] - xRange[0]) * area.w;
    625 };
    626
    627 /**
    628  * Convert from data x coordinates to canvas/div Y coordinate and optional
    629  * axis. Uses the first axis by default.
    630  *
    631  * returns a single value or null if y is null.
    632  */
    633 Dygraph.prototype.toDomYCoord = function(y, axis) {
    634   var pct = this.toPercentYCoord(y, axis);
    635
    636   if (pct === null) {
    637     return null;
    638   }
    639   var area = this.plotter_.area;
    640   return area.y + pct * area.h;
    641 };
    642
    643 /**
    644  * Convert from canvas/div coords to data coordinates.
    645  * If specified, do this conversion for the coordinate system of a particular
    646  * axis. Uses the first axis by default.
    647  * Returns a two-element array: [X, Y].
    648  *
    649  * Note: use toDataXCoord instead of toDataCoords(x, null) and use toDataYCoord
    650  * instead of toDataCoords(null, y, axis).
    651  */
    652 Dygraph.prototype.toDataCoords = function(x, y, axis) {
    653   return [ this.toDataXCoord(x), this.toDataYCoord(y, axis) ];
    654 };
    655
    656 /**
    657  * Convert from canvas/div x coordinate to data coordinate.
    658  *
    659  * If x is null, this returns null.
    660  */
    661 Dygraph.prototype.toDataXCoord = function(x) {
    662   if (x === null) {
    663     return null;
    664   }
    665
    666   var area = this.plotter_.area;
    667   var xRange = this.xAxisRange();
    668
    669   if (!this.attributes_.getForAxis("logscale", 'x')) {
    670     return xRange[0] + (x - area.x) / area.w * (xRange[1] - xRange[0]);
    671   } else {
    672     var pct = (x - area.x) / area.w;
    673     return utils.logRangeFraction(xRange[0], xRange[1], pct);
    674   }
    675 };
    676
    677 /**
    678  * Convert from canvas/div y coord to value.
    679  *
    680  * If y is null, this returns null.
    681  * if axis is null, this uses the first axis.
    682  */
    683 Dygraph.prototype.toDataYCoord = function(y, axis) {
    684   if (y === null) {
    685     return null;
    686   }
    687
    688   var area = this.plotter_.area;
    689   var yRange = this.yAxisRange(axis);
    690
    691   if (typeof(axis) == "undefined") axis = 0;
    692   if (!this.attributes_.getForAxis("logscale", axis)) {
    693     return yRange[0] + (area.y + area.h - y) / area.h * (yRange[1] - yRange[0]);
    694   } else {
    695     // Computing the inverse of toDomCoord.
    696     var pct = (y - area.y) / area.h;
    697     // Note reversed yRange, y1 is on top with pct==0.
    698     return utils.logRangeFraction(yRange[1], yRange[0], pct);
    699   }
    700 };
    701
    702 /**
    703  * Converts a y for an axis to a percentage from the top to the
    704  * bottom of the drawing area.
    705  *
    706  * If the coordinate represents a value visible on the canvas, then
    707  * the value will be between 0 and 1, where 0 is the top of the canvas.
    708  * However, this method will return values outside the range, as
    709  * values can fall outside the canvas.
    710  *
    711  * If y is null, this returns null.
    712  * if axis is null, this uses the first axis.
    713  *
    714  * @param {number} y The data y-coordinate.
    715  * @param {number} [axis] The axis number on which the data coordinate lives.
    716  * @return {number} A fraction in [0, 1] where 0 = the top edge.
    717  */
    718 Dygraph.prototype.toPercentYCoord = function(y, axis) {
    719   if (y === null) {
    720     return null;
    721   }
    722   if (typeof(axis) == "undefined") axis = 0;
    723
    724   var yRange = this.yAxisRange(axis);
    725
    726   var pct;
    727   var logscale = this.attributes_.getForAxis("logscale", axis);
    728   if (logscale) {
    729     var logr0 = utils.log10(yRange[0]);
    730     var logr1 = utils.log10(yRange[1]);
    731     pct = (logr1 - utils.log10(y)) / (logr1 - logr0);
    732   } else {
    733     // yRange[1] - y is unit distance from the bottom.
    734     // yRange[1] - yRange[0] is the scale of the range.
    735     // (yRange[1] - y) / (yRange[1] - yRange[0]) is the % from the bottom.
    736     pct = (yRange[1] - y) / (yRange[1] - yRange[0]);
    737   }
    738   return pct;
    739 };
    740
    741 /**
    742  * Converts an x value to a percentage from the left to the right of
    743  * the drawing area.
    744  *
    745  * If the coordinate represents a value visible on the canvas, then
    746  * the value will be between 0 and 1, where 0 is the left of the canvas.
    747  * However, this method will return values outside the range, as
    748  * values can fall outside the canvas.
    749  *
    750  * If x is null, this returns null.
    751  * @param {number} x The data x-coordinate.
    752  * @return {number} A fraction in [0, 1] where 0 = the left edge.
    753  */
    754 Dygraph.prototype.toPercentXCoord = function(x) {
    755   if (x === null) {
    756     return null;
    757   }
    758
    759   var xRange = this.xAxisRange();
    760   var pct;
    761   var logscale = this.attributes_.getForAxis("logscale", 'x') ;
    762   if (logscale === true) {  // logscale can be null so we test for true explicitly.
    763     var logr0 = utils.log10(xRange[0]);
    764     var logr1 = utils.log10(xRange[1]);
    765     pct = (utils.log10(x) - logr0) / (logr1 - logr0);
    766   } else {
    767     // x - xRange[0] is unit distance from the left.
    768     // xRange[1] - xRange[0] is the scale of the range.
    769     // The full expression below is the % from the left.
    770     pct = (x - xRange[0]) / (xRange[1] - xRange[0]);
    771   }
    772   return pct;
    773 };
    774
    775 /**
    776  * Returns the number of columns (including the independent variable).
    777  * @return {number} The number of columns.
    778  */
    779 Dygraph.prototype.numColumns = function() {
    780   if (!this.rawData_) return 0;
    781   return this.rawData_[0] ? this.rawData_[0].length : this.attr_("labels").length;
    782 };
    783
    784 /**
    785  * Returns the number of rows (excluding any header/label row).
    786  * @return {number} The number of rows, less any header.
    787  */
    788 Dygraph.prototype.numRows = function() {
    789   if (!this.rawData_) return 0;
    790   return this.rawData_.length;
    791 };
    792
    793 /**
    794  * Returns the value in the given row and column. If the row and column exceed
    795  * the bounds on the data, returns null. Also returns null if the value is
    796  * missing.
    797  * @param {number} row The row number of the data (0-based). Row 0 is the
    798  *     first row of data, not a header row.
    799  * @param {number} col The column number of the data (0-based)
    800  * @return {number} The value in the specified cell or null if the row/col
    801  *     were out of range.
    802  */
    803 Dygraph.prototype.getValue = function(row, col) {
    804   if (row < 0 || row >= this.rawData_.length) return null;
    805   if (col < 0 || col >= this.rawData_[row].length) return null;
    806
    807   return this.rawData_[row][col];
    808 };
    809
    810 /**
    811  * Generates interface elements for the Dygraph: a containing div, a div to
    812  * display the current point, and a textbox to adjust the rolling average
    813  * period. Also creates the Renderer/Layout elements.
    814  * @private
    815  */
    816 Dygraph.prototype.createInterface_ = function() {
    817   // Create the all-enclosing graph div
    818   var enclosing = this.maindiv_;
    819
    820   this.graphDiv = document.createElement("div");
    821
    822   // TODO(danvk): any other styles that are useful to set here?
    823   this.graphDiv.style.textAlign = 'left';  // This is a CSS "reset"
    824   this.graphDiv.style.position = 'relative';
    825   enclosing.appendChild(this.graphDiv);
    826
    827   // Create the canvas for interactive parts of the chart.
    828   this.canvas_ = utils.createCanvas();
    829   this.canvas_.style.position = "absolute";
    830   this.canvas_.style.top = 0;
    831   this.canvas_.style.left = 0;
    832
    833   // ... and for static parts of the chart.
    834   this.hidden_ = this.createPlotKitCanvas_(this.canvas_);
    835
    836   this.canvas_ctx_ = utils.getContext(this.canvas_);
    837   this.hidden_ctx_ = utils.getContext(this.hidden_);
    838
    839   this.resizeElements_();
    840
    841   // The interactive parts of the graph are drawn on top of the chart.
    842   this.graphDiv.appendChild(this.hidden_);
    843   this.graphDiv.appendChild(this.canvas_);
    844   this.mouseEventElement_ = this.createMouseEventElement_();
    845
    846   // Create the grapher
    847   this.layout_ = new DygraphLayout(this);
    848
    849   var dygraph = this;
    850
    851   this.mouseMoveHandler_ = function(e) {
    852     dygraph.mouseMove_(e);
    853   };
    854
    855   this.mouseOutHandler_ = function(e) {
    856     // The mouse has left the chart if:
    857     // 1. e.target is inside the chart
    858     // 2. e.relatedTarget is outside the chart
    859     var target = e.target || e.fromElement;
    860     var relatedTarget = e.relatedTarget || e.toElement;
    861     if (utils.isNodeContainedBy(target, dygraph.graphDiv) &&
    862         !utils.isNodeContainedBy(relatedTarget, dygraph.graphDiv)) {
    863       dygraph.mouseOut_(e);
    864     }
    865   };
    866
    867   this.addAndTrackEvent(window, 'mouseout', this.mouseOutHandler_);
    868   this.addAndTrackEvent(this.mouseEventElement_, 'mousemove', this.mouseMoveHandler_);
    869
    870   // Don't recreate and register the resize handler on subsequent calls.
    871   // This happens when the graph is resized.
    872   if (!this.resizeHandler_) {
    873     this.resizeHandler_ = function(e) {
    874       dygraph.resize();
    875     };
    876
    877     // Update when the window is resized.
    878     // TODO(danvk): drop frames depending on complexity of the chart.
    879     this.addAndTrackEvent(window, 'resize', this.resizeHandler_);
    880
    881     this.resizeObserver_ = null;
    882     var resizeMode = this.getStringOption('resizable');
    883     if ((typeof(ResizeObserver) === 'undefined') &&
    884         (resizeMode !== "no")) {
    885       console.error('ResizeObserver unavailable; ignoring resizable property');
    886       resizeMode = "no";
    887     }
    888     if (resizeMode === "horizontal" ||
    889         resizeMode === "vertical" ||
    890         resizeMode === "both") {
    891       enclosing.style.resize = resizeMode;
    892     } else if (resizeMode !== "passive") {
    893       resizeMode = "no";
    894     }
    895     if (resizeMode !== "no") {
    896       const maindivOverflow = window.getComputedStyle(enclosing).overflow;
    897       if (window.getComputedStyle(enclosing).overflow === 'visible')
    898         enclosing.style.overflow = 'hidden';
    899       this.resizeObserver_ = new ResizeObserver(this.resizeHandler_);
    900       this.resizeObserver_.observe(enclosing);
    901     }
    902   }
    903 };
    904
    905 Dygraph.prototype.resizeElements_ = function() {
    906   this.graphDiv.style.width = this.width_ + "px";
    907   this.graphDiv.style.height = this.height_ + "px";
    908
    909   var pixelRatioOption = this.getNumericOption('pixelRatio')
    910
    911   var canvasScale = pixelRatioOption || utils.getContextPixelRatio(this.canvas_ctx_);
    912   this.canvas_.width = this.width_ * canvasScale;
    913   this.canvas_.height = this.height_ * canvasScale;
    914   this.canvas_.style.width = this.width_ + "px";    // for IE
    915   this.canvas_.style.height = this.height_ + "px";  // for IE
    916   if (canvasScale !== 1) {
    917     this.canvas_ctx_.scale(canvasScale, canvasScale);
    918   }
    919
    920   var hiddenScale = pixelRatioOption || utils.getContextPixelRatio(this.hidden_ctx_);
    921   this.hidden_.width = this.width_ * hiddenScale;
    922   this.hidden_.height = this.height_ * hiddenScale;
    923   this.hidden_.style.width = this.width_ + "px";    // for IE
    924   this.hidden_.style.height = this.height_ + "px";  // for IE
    925   if (hiddenScale !== 1) {
    926     this.hidden_ctx_.scale(hiddenScale, hiddenScale);
    927   }
    928 };
    929
    930 /**
    931  * Detach DOM elements in the dygraph and null out all data references.
    932  * Calling this when you're done with a dygraph can dramatically reduce memory
    933  * usage. See, e.g., the tests/perf.html example.
    934  */
    935 Dygraph.prototype.destroy = function() {
    936   this.canvas_ctx_.restore();
    937   this.hidden_ctx_.restore();
    938
    939   // Destroy any plugins, in the reverse order that they were registered.
    940   for (var i = this.plugins_.length - 1; i >= 0; i--) {
    941     var p = this.plugins_.pop();
    942     if (p.plugin.destroy) p.plugin.destroy();
    943   }
    944
    945   var removeRecursive = function(node) {
    946     while (node.hasChildNodes()) {
    947       removeRecursive(node.firstChild);
    948       node.removeChild(node.firstChild);
    949     }
    950   };
    951
    952   this.removeTrackedEvents_();
    953
    954   // remove mouse event handlers (This may not be necessary anymore)
    955   utils.removeEvent(window, 'mouseout', this.mouseOutHandler_);
    956   utils.removeEvent(this.mouseEventElement_, 'mousemove', this.mouseMoveHandler_);
    957
    958   // dispose of resizing handlers
    959   if (this.resizeObserver_) {
    960     this.resizeObserver_.disconnect();
    961     this.resizeObserver_ = null;
    962   }
    963   utils.removeEvent(window, 'resize', this.resizeHandler_);
    964   this.resizeHandler_ = null;
    965
    966   removeRecursive(this.maindiv_);
    967
    968   var nullOut = function nullOut(obj) {
    969     for (var n in obj) {
    970       if (typeof(obj[n]) === 'object') {
    971         obj[n] = null;
    972       }
    973     }
    974   };
    975   // These may not all be necessary, but it can't hurt...
    976   nullOut(this.layout_);
    977   nullOut(this.plotter_);
    978   nullOut(this);
    979 };
    980
    981 /**
    982  * Creates the canvas on which the chart will be drawn. Only the Renderer ever
    983  * draws on this particular canvas. All Dygraph work (i.e. drawing hover dots
    984  * or the zoom rectangles) is done on this.canvas_.
    985  * @param {Object} canvas The Dygraph canvas over which to overlay the plot
    986  * @return {Object} The newly-created canvas
    987  * @private
    988  */
    989 Dygraph.prototype.createPlotKitCanvas_ = function(canvas) {
    990   var h = utils.createCanvas();
    991   h.style.position = "absolute";
    992   // TODO(danvk): h should be offset from canvas. canvas needs to include
    993   // some extra area to make it easier to zoom in on the far left and far
    994   // right. h needs to be precisely the plot area, so that clipping occurs.
    995   h.style.top = canvas.style.top;
    996   h.style.left = canvas.style.left;
    997   h.width = this.width_;
    998   h.height = this.height_;
    999   h.style.width = this.width_ + "px";    // for IE
    1000   h.style.height = this.height_ + "px";  // for IE
    1001   return h;
    1002 };
    1003
    1004 /**
    1005  * Creates an overlay element used to handle mouse events.
    1006  * @return {Object} The mouse event element.
    1007  * @private
    1008  */
    1009 Dygraph.prototype.createMouseEventElement_ = function() {
    1010   return this.canvas_;
    1011 };
    1012
    1013 /**
    1014  * Generate a set of distinct colors for the data series. This is done with a
    1015  * color wheel. Saturation/Value are customizable, and the hue is
    1016  * equally-spaced around the color wheel. If a custom set of colors is
    1017  * specified, that is used instead.
    1018  * @private
    1019  */
    1020 Dygraph.prototype.setColors_ = function() {
    1021   var labels = this.getLabels();
    1022   var num = labels.length - 1;
    1023   this.colors_ = [];
    1024   this.colorsMap_ = {};
    1025
    1026   // These are used for when no custom colors are specified.
    1027   var sat = this.getNumericOption('colorSaturation') || 1.0;
    1028   var val = this.getNumericOption('colorValue') || 0.5;
    1029   var half = Math.ceil(num / 2);
    1030
    1031   var colors = this.getOption('colors');
    1032   var visibility = this.visibility();
    1033   for (var i = 0; i < num; i++) {
    1034     if (!visibility[i]) {
    1035       continue;
    1036     }
    1037     var label = labels[i + 1];
    1038     var colorStr = this.attributes_.getForSeries('color', label);
    1039     if (!colorStr) {
    1040       if (colors) {
    1041         colorStr = colors[i % colors.length];
    1042       } else {
    1043         // alternate colors for high contrast.
    1044         var idx = i % 2 ? (half + (i + 1)/ 2) : Math.ceil((i + 1) / 2);
    1045         var hue = (1.0 * idx / (1 + num));
    1046         colorStr = utils.hsvToRGB(hue, sat, val);
    1047       }
    1048     }
    1049     this.colors_.push(colorStr);
    1050     this.colorsMap_[label] = colorStr;
    1051   }
    1052 };
    1053
    1054 /**
    1055  * Return the list of colors. This is either the list of colors passed in the
    1056  * attributes or the autogenerated list of rgb(r,g,b) strings.
    1057  * This does not return colors for invisible series.
    1058  * @return {Array.<string>} The list of colors.
    1059  */
    1060 Dygraph.prototype.getColors = function() {
    1061   return this.colors_;
    1062 };
    1063
    1064 /**
    1065  * Returns a few attributes of a series, i.e. its color, its visibility, which
    1066  * axis it's assigned to, and its column in the original data.
    1067  * Returns null if the series does not exist.
    1068  * Otherwise, returns an object with column, visibility, color and axis properties.
    1069  * The "axis" property will be set to 1 for y1 and 2 for y2.
    1070  * The "column" property can be fed back into getValue(row, column) to get
    1071  * values for this series.
    1072  */
    1073 Dygraph.prototype.getPropertiesForSeries = function(series_name) {
    1074   var idx = -1;
    1075   var labels = this.getLabels();
    1076   for (var i = 1; i < labels.length; i++) {
    1077     if (labels[i] == series_name) {
    1078       idx = i;
    1079       break;
    1080     }
    1081   }
    1082   if (idx == -1) return null;
    1083
    1084   return {
    1085     name: series_name,
    1086     column: idx,
    1087     visible: this.visibility()[idx - 1],
    1088     color: this.colorsMap_[series_name],
    1089     axis: 1 + this.attributes_.axisForSeries(series_name)
    1090   };
    1091 };
    1092
    1093 /**
    1094  * Create the text box to adjust the averaging period
    1095  * @private
    1096  */
    1097 Dygraph.prototype.createRollInterface_ = function() {
    1098   // Create a roller if one doesn't exist already.
    1099   var roller = this.roller_;
    1100   if (!roller) {
    1101     this.roller_ = roller = document.createElement("input");
    1102     roller.type = "text";
    1103     roller.style.display = "none";
    1104     roller.className = 'dygraph-roller';
    1105     this.graphDiv.appendChild(roller);
    1106   }
    1107
    1108   var display = this.getBooleanOption('showRoller') ? 'block' : 'none';
    1109
    1110   var area = this.getArea();
    1111   var textAttr = {
    1112                    "top": (area.y + area.h - 25) + "px",
    1113                    "left": (area.x + 1) + "px",
    1114                    "display": display
    1115                  };
    1116   roller.size = "2";
    1117   roller.value = this.rollPeriod_;
    1118   utils.update(roller.style, textAttr);
    1119
    1120   const that = this;
    1121   roller.onchange = function onchange() {
    1122     return that.adjustRoll(roller.value);
    1123   };
    1124 };
    1125
    1126 /**
    1127  * Set up all the mouse handlers needed to capture dragging behavior for zoom
    1128  * events.
    1129  * @private
    1130  */
    1131 Dygraph.prototype.createDragInterface_ = function() {
    1132   var context = {
    1133     // Tracks whether the mouse is down right now
    1134     isZooming: false,
    1135     isPanning: false,  // is this drag part of a pan?
    1136     is2DPan: false,    // if so, is that pan 1- or 2-dimensional?
    1137     dragStartX: null, // pixel coordinates
    1138     dragStartY: null, // pixel coordinates
    1139     dragEndX: null, // pixel coordinates
    1140     dragEndY: null, // pixel coordinates
    1141     dragDirection: null,
    1142     prevEndX: null, // pixel coordinates
    1143     prevEndY: null, // pixel coordinates
    1144     prevDragDirection: null,
    1145     cancelNextDblclick: false,  // see comment in dygraph-interaction-model.js
    1146
    1147     // The value on the left side of the graph when a pan operation starts.
    1148     initialLeftmostDate: null,
    1149
    1150     // The number of units each pixel spans. (This won't be valid for log
    1151     // scales)
    1152     xUnitsPerPixel: null,
    1153
    1154     // TODO(danvk): update this comment
    1155     // The range in second/value units that the viewport encompasses during a
    1156     // panning operation.
    1157     dateRange: null,
    1158
    1159     // Top-left corner of the canvas, in DOM coords
    1160     // TODO(konigsberg): Rename topLeftCanvasX, topLeftCanvasY.
    1161     px: 0,
    1162     py: 0,
    1163
    1164     // Values for use with panEdgeFraction, which limit how far outside the
    1165     // graph's data boundaries it can be panned.
    1166     boundedDates: null, // [minDate, maxDate]
    1167     boundedValues: null, // [[minValue, maxValue] ...]
    1168
    1169     // We cover iframes during mouse interactions. See comments in
    1170     // dygraph-utils.js for more info on why this is a good idea.
    1171     tarp: new IFrameTarp(),
    1172
    1173     // contextB is the same thing as this context object but renamed.
    1174     initializeMouseDown: function(event, g, contextB) {
    1175       // prevents mouse drags from selecting page text.
    1176       if (event.preventDefault) {
    1177         event.preventDefault();  // Firefox, Chrome, etc.
    1178       } else {
    1179         event.returnValue = false;  // IE
    1180         event.cancelBubble = true;
    1181       }
    1182
    1183       var canvasPos = utils.findPos(g.canvas_);
    1184       contextB.px = canvasPos.x;
    1185       contextB.py = canvasPos.y;
    1186       contextB.dragStartX = utils.dragGetX_(event, contextB);
    1187       contextB.dragStartY = utils.dragGetY_(event, contextB);
    1188       contextB.cancelNextDblclick = false;
    1189       contextB.tarp.cover();
    1190     },
    1191     destroy: function() {
    1192       var context = this;
    1193       if (context.isZooming || context.isPanning) {
    1194         context.isZooming = false;
    1195         context.dragStartX = null;
    1196         context.dragStartY = null;
    1197       }
    1198
    1199       if (context.isPanning) {
    1200         context.isPanning = false;
    1201         context.draggingDate = null;
    1202         context.dateRange = null;
    1203         for (var i = 0; i < self.axes_.length; i++) {
    1204           delete self.axes_[i].draggingValue;
    1205           delete self.axes_[i].dragValueRange;
    1206         }
    1207       }
    1208
    1209       context.tarp.uncover();
    1210     }
    1211   };
    1212
    1213   var interactionModel = this.getOption("interactionModel");
    1214
    1215   // Self is the graph.
    1216   var self = this;
    1217
    1218   // Function that binds the graph and context to the handler.
    1219   var bindHandler = function(handler) {
    1220     return function(event) {
    1221       handler(event, self, context);
    1222     };
    1223   };
    1224
    1225   for (var eventName in interactionModel) {
    1226     if (!interactionModel.hasOwnProperty(eventName)) continue;
    1227     this.addAndTrackEvent(this.mouseEventElement_, eventName,
    1228         bindHandler(interactionModel[eventName]));
    1229   }
    1230
    1231   // If the user releases the mouse button during a drag, but not over the
    1232   // canvas, then it doesn't count as a zooming action.
    1233   if (!interactionModel.willDestroyContextMyself) {
    1234     var mouseUpHandler = function(event) {
    1235       context.destroy();
    1236     };
    1237
    1238     this.addAndTrackEvent(document, 'mouseup', mouseUpHandler);
    1239   }
    1240 };
    1241
    1242 /**
    1243  * Draw a gray zoom rectangle over the desired area of the canvas. Also clears
    1244  * up any previous zoom rectangles that were drawn. This could be optimized to
    1245  * avoid extra redrawing, but it's tricky to avoid interactions with the status
    1246  * dots.
    1247  *
    1248  * @param {number} direction the direction of the zoom rectangle. Acceptable
    1249  *     values are utils.HORIZONTAL and utils.VERTICAL.
    1250  * @param {number} startX The X position where the drag started, in canvas
    1251  *     coordinates.
    1252  * @param {number} endX The current X position of the drag, in canvas coords.
    1253  * @param {number} startY The Y position where the drag started, in canvas
    1254  *     coordinates.
    1255  * @param {number} endY The current Y position of the drag, in canvas coords.
    1256  * @param {number} prevDirection the value of direction on the previous call to
    1257  *     this function. Used to avoid excess redrawing
    1258  * @param {number} prevEndX The value of endX on the previous call to this
    1259  *     function. Used to avoid excess redrawing
    1260  * @param {number} prevEndY The value of endY on the previous call to this
    1261  *     function. Used to avoid excess redrawing
    1262  * @private
    1263  */
    1264 Dygraph.prototype.drawZoomRect_ = function(direction, startX, endX, startY,
    1265                                            endY, prevDirection, prevEndX,
    1266                                            prevEndY) {
    1267   var ctx = this.canvas_ctx_;
    1268
    1269   // Clean up from the previous rect if necessary
    1270   if (prevDirection == utils.HORIZONTAL) {
    1271     ctx.clearRect(Math.min(startX, prevEndX), this.layout_.getPlotArea().y,
    1272                   Math.abs(startX - prevEndX), this.layout_.getPlotArea().h);
    1273   } else if (prevDirection == utils.VERTICAL) {
    1274     ctx.clearRect(this.layout_.getPlotArea().x, Math.min(startY, prevEndY),
    1275                   this.layout_.getPlotArea().w, Math.abs(startY - prevEndY));
    1276   }
    1277
    1278   // Draw a light-grey rectangle to show the new viewing area
    1279   if (direction == utils.HORIZONTAL) {
    1280     if (endX && startX) {
    1281       ctx.fillStyle = "rgba(128,128,128,0.33)";
    1282       ctx.fillRect(Math.min(startX, endX), this.layout_.getPlotArea().y,
    1283                    Math.abs(endX - startX), this.layout_.getPlotArea().h);
    1284     }
    1285   } else if (direction == utils.VERTICAL) {
    1286     if (endY && startY) {
    1287       ctx.fillStyle = "rgba(128,128,128,0.33)";
    1288       ctx.fillRect(this.layout_.getPlotArea().x, Math.min(startY, endY),
    1289                    this.layout_.getPlotArea().w, Math.abs(endY - startY));
    1290     }
    1291   }
    1292 };
    1293
    1294 /**
    1295  * Clear the zoom rectangle (and perform no zoom).
    1296  * @private
    1297  */
    1298 Dygraph.prototype.clearZoomRect_ = function() {
    1299   this.currentZoomRectArgs_ = null;
    1300   this.canvas_ctx_.clearRect(0, 0, this.width_, this.height_);
    1301 };
    1302
    1303 /**
    1304  * Zoom to something containing [lowX, highX]. These are pixel coordinates in
    1305  * the canvas. The exact zoom window may be slightly larger if there are no data
    1306  * points near lowX or highX. Don't confuse this function with doZoomXDates,
    1307  * which accepts dates that match the raw data. This function redraws the graph.
    1308  *
    1309  * @param {number} lowX The leftmost pixel value that should be visible.
    1310  * @param {number} highX The rightmost pixel value that should be visible.
    1311  * @private
    1312  */
    1313 Dygraph.prototype.doZoomX_ = function(lowX, highX) {
    1314   this.currentZoomRectArgs_ = null;
    1315   // Find the earliest and latest dates contained in this canvasx range.
    1316   // Convert the call to date ranges of the raw data.
    1317   var minDate = this.toDataXCoord(lowX);
    1318   var maxDate = this.toDataXCoord(highX);
    1319   this.doZoomXDates_(minDate, maxDate);
    1320 };
    1321
    1322 /**
    1323  * Zoom to something containing [minDate, maxDate] values. Don't confuse this
    1324  * method with doZoomX which accepts pixel coordinates. This function redraws
    1325  * the graph.
    1326  *
    1327  * @param {number} minDate The minimum date that should be visible.
    1328  * @param {number} maxDate The maximum date that should be visible.
    1329  * @private
    1330  */
    1331 Dygraph.prototype.doZoomXDates_ = function(minDate, maxDate) {
    1332   // TODO(danvk): when xAxisRange is null (i.e. "fit to data", the animation
    1333   // can produce strange effects. Rather than the x-axis transitioning slowly
    1334   // between values, it can jerk around.)
    1335   var old_window = this.xAxisRange();
    1336   var new_window = [minDate, maxDate];
    1337   const zoomCallback = this.getFunctionOption('zoomCallback');
    1338   const that = this;
    1339   this.doAnimatedZoom(old_window, new_window, null, null, function animatedZoomCallback() {
    1340     if (zoomCallback) {
    1341       zoomCallback.call(that, minDate, maxDate, that.yAxisRanges());
    1342     }
    1343   });
    1344 };
    1345
    1346 /**
    1347  * Zoom to something containing [lowY, highY]. These are pixel coordinates in
    1348  * the canvas. This function redraws the graph.
    1349  *
    1350  * @param {number} lowY The topmost pixel value that should be visible.
    1351  * @param {number} highY The lowest pixel value that should be visible.
    1352  * @private
    1353  */
    1354 Dygraph.prototype.doZoomY_ = function(lowY, highY) {
    1355   this.currentZoomRectArgs_ = null;
    1356   // Find the highest and lowest values in pixel range for each axis.
    1357   // Note that lowY (in pixels) corresponds to the max Value (in data coords).
    1358   // This is because pixels increase as you go down on the screen, whereas data
    1359   // coordinates increase as you go up the screen.
    1360   var oldValueRanges = this.yAxisRanges();
    1361   var newValueRanges = [];
    1362   for (var i = 0; i < this.axes_.length; i++) {
    1363     var hi = this.toDataYCoord(lowY, i);
    1364     var low = this.toDataYCoord(highY, i);
    1365     newValueRanges.push([low, hi]);
    1366   }
    1367
    1368   const zoomCallback = this.getFunctionOption('zoomCallback');
    1369   const that = this;
    1370   this.doAnimatedZoom(null, null, oldValueRanges, newValueRanges, function animatedZoomCallback() {
    1371     if (zoomCallback) {
    1372       const [minX, maxX] = that.xAxisRange();
    1373       zoomCallback.call(that, minX, maxX, that.yAxisRanges());
    1374     }
    1375   });
    1376 };
    1377
    1378 /**
    1379  * Transition function to use in animations. Returns values between 0.0
    1380  * (totally old values) and 1.0 (totally new values) for each frame.
    1381  * @private
    1382  */
    1383 Dygraph.zoomAnimationFunction = function(frame, numFrames) {
    1384   var k = 1.5;
    1385   return (1.0 - Math.pow(k, -frame)) / (1.0 - Math.pow(k, -numFrames));
    1386 };
    1387
    1388 /**
    1389  * Reset the zoom to the original view coordinates. This is the same as
    1390  * double-clicking on the graph.
    1391  */
    1392 Dygraph.prototype.resetZoom = function() {
    1393   const dirtyX = this.isZoomed('x');
    1394   const dirtyY = this.isZoomed('y');
    1395   const dirty = dirtyX || dirtyY;
    1396
    1397   // Clear any selection, since it's likely to be drawn in the wrong place.
    1398   this.clearSelection();
    1399
    1400   if (!dirty) return;
    1401
    1402   // Calculate extremes to avoid lack of padding on reset.
    1403   const [minDate, maxDate] = this.xAxisExtremes();
    1404
    1405   const animatedZooms = this.getBooleanOption('animatedZooms');
    1406   const zoomCallback = this.getFunctionOption('zoomCallback');
    1407
    1408   // TODO(danvk): merge this block w/ the code below.
    1409   // TODO(danvk): factor out a generic, public zoomTo method.
    1410   if (!animatedZooms) {
    1411     this.dateWindow_ = null;
    1412     this.axes_.forEach(axis => {
    1413       if (axis.valueRange) delete axis.valueRange;
    1414     });
    1415
    1416     this.drawGraph_();
    1417     if (zoomCallback) {
    1418       zoomCallback.call(this, minDate, maxDate, this.yAxisRanges());
    1419     }
    1420     return;
    1421   }
    1422
    1423   var oldWindow=null, newWindow=null, oldValueRanges=null, newValueRanges=null;
    1424   if (dirtyX) {
    1425     oldWindow = this.xAxisRange();
    1426     newWindow = [minDate, maxDate];
    1427   }
    1428
    1429   if (dirtyY) {
    1430     oldValueRanges = this.yAxisRanges();
    1431     newValueRanges = this.yAxisExtremes();
    1432   }
    1433
    1434   const that = this;
    1435   this.doAnimatedZoom(oldWindow, newWindow, oldValueRanges, newValueRanges,
    1436       function animatedZoomCallback() {
    1437         that.dateWindow_ = null;
    1438         that.axes_.forEach(axis => {
    1439           if (axis.valueRange) delete axis.valueRange;
    1440         });
    1441         if (zoomCallback) {
    1442           zoomCallback.call(that, minDate, maxDate, that.yAxisRanges());
    1443         }
    1444       });
    1445 };
    1446
    1447 /**
    1448  * Combined animation logic for all zoom functions.
    1449  * either the x parameters or y parameters may be null.
    1450  * @private
    1451  */
    1452 Dygraph.prototype.doAnimatedZoom = function(oldXRange, newXRange, oldYRanges, newYRanges, callback) {
    1453   var steps = this.getBooleanOption("animatedZooms") ?
    1454       Dygraph.ANIMATION_STEPS : 1;
    1455
    1456   var windows = [];
    1457   var valueRanges = [];
    1458   var step, frac;
    1459
    1460   if (oldXRange !== null && newXRange !== null) {
    1461     for (step = 1; step <= steps; step++) {
    1462       frac = Dygraph.zoomAnimationFunction(step, steps);
    1463       windows[step-1] = [oldXRange[0]*(1-frac) + frac*newXRange[0],
    1464                          oldXRange[1]*(1-frac) + frac*newXRange[1]];
    1465     }
    1466   }
    1467
    1468   if (oldYRanges !== null && newYRanges !== null) {
    1469     for (step = 1; step <= steps; step++) {
    1470       frac = Dygraph.zoomAnimationFunction(step, steps);
    1471       var thisRange = [];
    1472       for (var j = 0; j < this.axes_.length; j++) {
    1473         thisRange.push([oldYRanges[j][0]*(1-frac) + frac*newYRanges[j][0],
    1474                         oldYRanges[j][1]*(1-frac) + frac*newYRanges[j][1]]);
    1475       }
    1476       valueRanges[step-1] = thisRange;
    1477     }
    1478   }
    1479
    1480   const that = this;
    1481   utils.repeatAndCleanup(function (step) {
    1482     if (valueRanges.length) {
    1483       for (var i = 0; i < that.axes_.length; i++) {
    1484         var w = valueRanges[step][i];
    1485         that.axes_[i].valueRange = [w[0], w[1]];
    1486       }
    1487     }
    1488     if (windows.length) {
    1489       that.dateWindow_ = windows[step];
    1490     }
    1491     that.drawGraph_();
    1492   }, steps, Dygraph.ANIMATION_DURATION / steps, callback);
    1493 };
    1494
    1495 /**
    1496  * Get the current graph's area object.
    1497  *
    1498  * Returns: {x, y, w, h}
    1499  */
    1500 Dygraph.prototype.getArea = function() {
    1501   return this.plotter_.area;
    1502 };
    1503
    1504 /**
    1505  * Convert a mouse event to DOM coordinates relative to the graph origin.
    1506  *
    1507  * Returns a two-element array: [X, Y].
    1508  */
    1509 Dygraph.prototype.eventToDomCoords = function(event) {
    1510   if (event.offsetX && event.offsetY) {
    1511     return [ event.offsetX, event.offsetY ];
    1512   } else {
    1513     var eventElementPos = utils.findPos(this.mouseEventElement_);
    1514     var canvasx = utils.pageX(event) - eventElementPos.x;
    1515     var canvasy = utils.pageY(event) - eventElementPos.y;
    1516     return [canvasx, canvasy];
    1517   }
    1518 };
    1519
    1520 /**
    1521  * Given a canvas X coordinate, find the closest row.
    1522  * @param {number} domX graph-relative DOM X coordinate
    1523  * Returns {number} row number.
    1524  * @private
    1525  */
    1526 Dygraph.prototype.findClosestRow = function(domX) {
    1527   var minDistX = Infinity;
    1528   var closestRow = -1;
    1529   var sets = this.layout_.points;
    1530   for (var i = 0; i < sets.length; i++) {
    1531     var points = sets[i];
    1532     var len = points.length;
    1533     for (var j = 0; j < len; j++) {
    1534       var point = points[j];
    1535       if (!utils.isValidPoint(point, true)) continue;
    1536       var dist = Math.abs(point.canvasx - domX);
    1537       if (dist < minDistX) {
    1538         minDistX = dist;
    1539         closestRow = point.idx;
    1540       }
    1541     }
    1542   }
    1543
    1544   return closestRow;
    1545 };
    1546
    1547 /**
    1548  * Given canvas X,Y coordinates, find the closest point.
    1549  *
    1550  * This finds the individual data point across all visible series
    1551  * that's closest to the supplied DOM coordinates using the standard
    1552  * Euclidean X,Y distance.
    1553  *
    1554  * @param {number} domX graph-relative DOM X coordinate
    1555  * @param {number} domY graph-relative DOM Y coordinate
    1556  * Returns: {row, seriesName, point}
    1557  * @private
    1558  */
    1559 Dygraph.prototype.findClosestPoint = function(domX, domY) {
    1560   var minDist = Infinity;
    1561   var dist, dx, dy, point, closestPoint, closestSeries, closestRow;
    1562   for ( var setIdx = this.layout_.points.length - 1 ; setIdx >= 0 ; --setIdx ) {
    1563     var points = this.layout_.points[setIdx];
    1564     for (var i = 0; i < points.length; ++i) {
    1565       point = points[i];
    1566       if (!utils.isValidPoint(point)) continue;
    1567       dx = point.canvasx - domX;
    1568       dy = point.canvasy - domY;
    1569       dist = dx * dx + dy * dy;
    1570       if (dist < minDist) {
    1571         minDist = dist;
    1572         closestPoint = point;
    1573         closestSeries = setIdx;
    1574         closestRow = point.idx;
    1575       }
    1576     }
    1577   }
    1578   var name = this.layout_.setNames[closestSeries];
    1579   return {
    1580     row: closestRow,
    1581     seriesName: name,
    1582     point: closestPoint
    1583   };
    1584 };
    1585
    1586 /**
    1587  * Given canvas X,Y coordinates, find the touched area in a stacked graph.
    1588  *
    1589  * This first finds the X data point closest to the supplied DOM X coordinate,
    1590  * then finds the series which puts the Y coordinate on top of its filled area,
    1591  * using linear interpolation between adjacent point pairs.
    1592  *
    1593  * @param {number} domX graph-relative DOM X coordinate
    1594  * @param {number} domY graph-relative DOM Y coordinate
    1595  * Returns: {row, seriesName, point}
    1596  * @private
    1597  */
    1598 Dygraph.prototype.findStackedPoint = function(domX, domY) {
    1599   var row = this.findClosestRow(domX);
    1600   var closestPoint, closestSeries;
    1601   for (var setIdx = 0; setIdx < this.layout_.points.length; ++setIdx) {
    1602     var boundary = this.getLeftBoundary_(setIdx);
    1603     var rowIdx = row - boundary;
    1604     var points = this.layout_.points[setIdx];
    1605     if (rowIdx >= points.length) continue;
    1606     var p1 = points[rowIdx];
    1607     if (!utils.isValidPoint(p1)) continue;
    1608     var py = p1.canvasy;
    1609     if (domX > p1.canvasx && rowIdx + 1 < points.length) {
    1610       // interpolate series Y value using next point
    1611       var p2 = points[rowIdx + 1];
    1612       if (utils.isValidPoint(p2)) {
    1613         var dx = p2.canvasx - p1.canvasx;
    1614         if (dx > 0) {
    1615           var r = (domX - p1.canvasx) / dx;
    1616           py += r * (p2.canvasy - p1.canvasy);
    1617         }
    1618       }
    1619     } else if (domX < p1.canvasx && rowIdx > 0) {
    1620       // interpolate series Y value using previous point
    1621       var p0 = points[rowIdx - 1];
    1622       if (utils.isValidPoint(p0)) {
    1623         var dx = p1.canvasx - p0.canvasx;
    1624         if (dx > 0) {
    1625           var r = (p1.canvasx - domX) / dx;
    1626           py += r * (p0.canvasy - p1.canvasy);
    1627         }
    1628       }
    1629     }
    1630     // Stop if the point (domX, py) is above this series' upper edge
    1631     if (setIdx === 0 || py < domY) {
    1632       closestPoint = p1;
    1633       closestSeries = setIdx;
    1634     }
    1635   }
    1636   var name = this.layout_.setNames[closestSeries];
    1637   return {
    1638     row: row,
    1639     seriesName: name,
    1640     point: closestPoint
    1641   };
    1642 };
    1643
    1644 /**
    1645  * When the mouse moves in the canvas, display information about a nearby data
    1646  * point and draw dots over those points in the data series. This function
    1647  * takes care of cleanup of previously-drawn dots.
    1648  * @param {Object} event The mousemove event from the browser.
    1649  * @private
    1650  */
    1651 Dygraph.prototype.mouseMove_ = function(event) {
    1652   // This prevents JS errors when mousing over the canvas before data loads.
    1653   var points = this.layout_.points;
    1654   if (points === undefined || points === null) return;
    1655
    1656   var canvasCoords = this.eventToDomCoords(event);
    1657   var canvasx = canvasCoords[0];
    1658   var canvasy = canvasCoords[1];
    1659
    1660   var highlightSeriesOpts = this.getOption("highlightSeriesOpts");
    1661   var selectionChanged = false;
    1662   if (highlightSeriesOpts && !this.isSeriesLocked()) {
    1663     var closest;
    1664     if (this.getBooleanOption("stackedGraph")) {
    1665       closest = this.findStackedPoint(canvasx, canvasy);
    1666     } else {
    1667       closest = this.findClosestPoint(canvasx, canvasy);
    1668     }
    1669     selectionChanged = this.setSelection(closest.row, closest.seriesName);
    1670   } else {
    1671     var idx = this.findClosestRow(canvasx);
    1672     selectionChanged = this.setSelection(idx);
    1673   }
    1674
    1675   var callback = this.getFunctionOption("highlightCallback");
    1676   if (callback && selectionChanged) {
    1677     callback.call(this, event,
    1678         this.lastx_,
    1679         this.selPoints_,
    1680         this.lastRow_,
    1681         this.highlightSet_);
    1682   }
    1683 };
    1684
    1685 /**
    1686  * Fetch left offset from the specified set index or if not passed, the
    1687  * first defined boundaryIds record (see bug #236).
    1688  * @private
    1689  */
    1690 Dygraph.prototype.getLeftBoundary_ = function(setIdx) {
    1691   if (this.boundaryIds_[setIdx]) {
    1692       return this.boundaryIds_[setIdx][0];
    1693   } else {
    1694     for (var i = 0; i < this.boundaryIds_.length; i++) {
    1695       if (this.boundaryIds_[i] !== undefined) {
    1696         return this.boundaryIds_[i][0];
    1697       }
    1698     }
    1699     return 0;
    1700   }
    1701 };
    1702
    1703 Dygraph.prototype.animateSelection_ = function(direction) {
    1704   var totalSteps = 10;
    1705   var millis = 30;
    1706   if (this.fadeLevel === undefined) this.fadeLevel = 0;
    1707   if (this.animateId === undefined) this.animateId = 0;
    1708   var start = this.fadeLevel;
    1709   var steps = direction < 0 ? start : totalSteps - start;
    1710   if (steps <= 0) {
    1711     if (this.fadeLevel) {
    1712       this.updateSelection_(1.0);
    1713     }
    1714     return;
    1715   }
    1716
    1717   var thisId = ++this.animateId;
    1718   var that = this;
    1719
    1720   utils.repeatAndCleanup(
    1721     function(step) {
    1722       // ignore simultaneous animations
    1723       if (that.animateId != thisId) return;
    1724
    1725       that.fadeLevel = start + (step + 1) * direction;
    1726       if (that.fadeLevel === 0) {
    1727         that.clearSelection();
    1728       } else {
    1729         that.updateSelection_(that.fadeLevel / totalSteps);
    1730       }
    1731     },
    1732     steps, millis, function() {});
    1733 };
    1734
    1735 /**
    1736  * Draw dots over the selectied points in the data series. This function
    1737  * takes care of cleanup of previously-drawn dots.
    1738  * @private
    1739  */
    1740 Dygraph.prototype.updateSelection_ = function(opt_animFraction) {
    1741   /*var defaultPrevented = */
    1742   this.cascadeEvents_('select', {
    1743     selectedRow: this.lastRow_ === -1 ? undefined : this.lastRow_,
    1744     selectedX: this.lastx_ === null ? undefined : this.lastx_,
    1745     selectedPoints: this.selPoints_
    1746   });
    1747   // TODO(danvk): use defaultPrevented here?
    1748
    1749   // Clear the previously drawn vertical, if there is one
    1750   var i;
    1751   var ctx = this.canvas_ctx_;
    1752   if (this.getOption('highlightSeriesOpts')) {
    1753     ctx.clearRect(0, 0, this.width_, this.height_);
    1754     var alpha = 1.0 - this.getNumericOption('highlightSeriesBackgroundAlpha');
    1755     var backgroundColor = utils.toRGB_(this.getOption('highlightSeriesBackgroundColor'));
    1756
    1757     if (alpha) {
    1758       // Activating background fade includes an animation effect for a gradual
    1759       // fade. TODO(klausw): make this independently configurable if it causes
    1760       // issues? Use a shared preference to control animations?
    1761       var animateBackgroundFade = this.getBooleanOption('animateBackgroundFade');
    1762       if (animateBackgroundFade) {
    1763         if (opt_animFraction === undefined) {
    1764           // start a new animation
    1765           this.animateSelection_(1);
    1766           return;
    1767         }
    1768         alpha *= opt_animFraction;
    1769       }
    1770       ctx.fillStyle = 'rgba(' + backgroundColor.r + ',' + backgroundColor.g + ',' + backgroundColor.b + ',' + alpha + ')';
    1771       ctx.fillRect(0, 0, this.width_, this.height_);
    1772     }
    1773
    1774     // Redraw only the highlighted series in the interactive canvas (not the
    1775     // static plot canvas, which is where series are usually drawn).
    1776     this.plotter_._renderLineChart(this.highlightSet_, ctx);
    1777   } else if (this.previousVerticalX_ >= 0) {
    1778     // Determine the maximum highlight circle size.
    1779     var maxCircleSize = 0;
    1780     var labels = this.attr_('labels');
    1781     for (i = 1; i < labels.length; i++) {
    1782       var r = this.getNumericOption('highlightCircleSize', labels[i]);
    1783       if (r > maxCircleSize) maxCircleSize = r;
    1784     }
    1785     var px = this.previousVerticalX_;
    1786     ctx.clearRect(px - maxCircleSize - 1, 0,
    1787                   2 * maxCircleSize + 2, this.height_);
    1788   }
    1789
    1790   if (this.selPoints_.length > 0) {
    1791     // Draw colored circles over the center of each selected point
    1792     var canvasx = this.selPoints_[0].canvasx;
    1793     ctx.save();
    1794     for (i = 0; i < this.selPoints_.length; i++) {
    1795       var pt = this.selPoints_[i];
    1796       if (isNaN(pt.canvasy)) continue;
    1797
    1798       var circleSize = this.getNumericOption('highlightCircleSize', pt.name);
    1799       var callback = this.getFunctionOption("drawHighlightPointCallback", pt.name);
    1800       var color = this.plotter_.colors[pt.name];
    1801       if (!callback) {
    1802         callback = utils.Circles.DEFAULT;
    1803       }
    1804       ctx.lineWidth = this.getNumericOption('strokeWidth', pt.name);
    1805       ctx.strokeStyle = color;
    1806       ctx.fillStyle = color;
    1807       callback.call(this, this, pt.name, ctx, canvasx, pt.canvasy,
    1808           color, circleSize, pt.idx);
    1809     }
    1810     ctx.restore();
    1811
    1812     this.previousVerticalX_ = canvasx;
    1813   }
    1814 };
    1815
    1816 /**
    1817  * Manually set the selected points and display information about them in the
    1818  * legend. The selection can be cleared using clearSelection() and queried
    1819  * using getSelection().
    1820  *
    1821  * To set a selected series but not a selected point, call setSelection with
    1822  * row=false and the selected series name.
    1823  *
    1824  * @param {number} row Row number that should be highlighted (i.e. appear with
    1825  * hover dots on the chart).
    1826  * @param {seriesName} optional series name to highlight that series with the
    1827  * the highlightSeriesOpts setting.
    1828  * @param {locked} optional If true, keep seriesName selected when mousing
    1829  * over the graph, disabling closest-series highlighting. Call clearSelection()
    1830  * to unlock it.
    1831  * @param {trigger_highlight_callback} optional If true, trigger any
    1832  * user-defined highlightCallback if highlightCallback has been set.
    1833  */
    1834 Dygraph.prototype.setSelection = function setSelection(row, opt_seriesName,
    1835                                                        opt_locked,
    1836                                                        opt_trigger_highlight_callback) {
    1837   // Extract the points we've selected
    1838   this.selPoints_ = [];
    1839
    1840   var changed = false;
    1841   if (row !== false && row >= 0) {
    1842     if (row != this.lastRow_) changed = true;
    1843     this.lastRow_ = row;
    1844     for (var setIdx = 0; setIdx < this.layout_.points.length; ++setIdx) {
    1845       var points = this.layout_.points[setIdx];
    1846       // Check if the point at the appropriate index is the point we're looking
    1847       // for.  If it is, just use it, otherwise search the array for a point
    1848       // in the proper place.
    1849       var setRow = row - this.getLeftBoundary_(setIdx);
    1850       if (setRow >= 0 && setRow < points.length && points[setRow].idx == row) {
    1851         var point = points[setRow];
    1852         if (point.yval !== null) this.selPoints_.push(point);
    1853       } else {
    1854         for (var pointIdx = 0; pointIdx < points.length; ++pointIdx) {
    1855           var point = points[pointIdx];
    1856           if (point.idx == row) {
    1857             if (point.yval !== null) {
    1858               this.selPoints_.push(point);
    1859             }
    1860             break;
    1861           }
    1862         }
    1863       }
    1864     }
    1865   } else {
    1866     if (this.lastRow_ >= 0) changed = true;
    1867     this.lastRow_ = -1;
    1868   }
    1869
    1870   if (this.selPoints_.length) {
    1871     this.lastx_ = this.selPoints_[0].xval;
    1872   } else {
    1873     this.lastx_ = null;
    1874   }
    1875
    1876   if (opt_seriesName !== undefined) {
    1877     if (this.highlightSet_ !== opt_seriesName) changed = true;
    1878     this.highlightSet_ = opt_seriesName;
    1879   }
    1880
    1881   if (opt_locked !== undefined) {
    1882     this.lockedSet_ = opt_locked;
    1883   }
    1884
    1885   if (changed) {
    1886     this.updateSelection_(undefined);
    1887
    1888     if (opt_trigger_highlight_callback) {
    1889       var callback = this.getFunctionOption("highlightCallback");
    1890       if (callback) {
    1891         var event = {};
    1892         callback.call(this, event,
    1893           this.lastx_,
    1894           this.selPoints_,
    1895           this.lastRow_,
    1896           this.highlightSet_);
    1897       }
    1898     }
    1899   }
    1900   return changed;
    1901 };
    1902
    1903 /**
    1904  * The mouse has left the canvas. Clear out whatever artifacts remain
    1905  * @param {Object} event the mouseout event from the browser.
    1906  * @private
    1907  */
    1908 Dygraph.prototype.mouseOut_ = function(event) {
    1909   if (this.getFunctionOption("unhighlightCallback")) {
    1910     this.getFunctionOption("unhighlightCallback").call(this, event);
    1911   }
    1912
    1913   if (this.getBooleanOption("hideOverlayOnMouseOut") && !this.lockedSet_) {
    1914     this.clearSelection();
    1915   }
    1916 };
    1917
    1918 /**
    1919  * Clears the current selection (i.e. points that were highlighted by moving
    1920  * the mouse over the chart).
    1921  */
    1922 Dygraph.prototype.clearSelection = function() {
    1923   this.cascadeEvents_('deselect', {});
    1924
    1925   this.lockedSet_ = false;
    1926   // Get rid of the overlay data
    1927   if (this.fadeLevel) {
    1928     this.animateSelection_(-1);
    1929     return;
    1930   }
    1931   this.canvas_ctx_.clearRect(0, 0, this.width_, this.height_);
    1932   this.fadeLevel = 0;
    1933   this.selPoints_ = [];
    1934   this.lastx_ = null;
    1935   this.lastRow_ = -1;
    1936   this.highlightSet_ = null;
    1937 };
    1938
    1939 /**
    1940  * Returns the number of the currently selected row. To get data for this row,
    1941  * you can use the getValue method.
    1942  * @return {number} row number, or -1 if nothing is selected
    1943  */
    1944 Dygraph.prototype.getSelection = function() {
    1945   if (!this.selPoints_ || this.selPoints_.length < 1) {
    1946     return -1;
    1947   }
    1948
    1949   for (var setIdx = 0; setIdx < this.layout_.points.length; setIdx++) {
    1950     var points = this.layout_.points[setIdx];
    1951     for (var row = 0; row < points.length; row++) {
    1952       if (points[row].x == this.selPoints_[0].x) {
    1953         return points[row].idx;
    1954       }
    1955     }
    1956   }
    1957   return -1;
    1958 };
    1959
    1960 /**
    1961  * Returns the name of the currently-highlighted series.
    1962  * Only available when the highlightSeriesOpts option is in use.
    1963  */
    1964 Dygraph.prototype.getHighlightSeries = function() {
    1965   return this.highlightSet_;
    1966 };
    1967
    1968 /**
    1969  * Returns true if the currently-highlighted series was locked
    1970  * via setSelection(..., seriesName, true).
    1971  */
    1972 Dygraph.prototype.isSeriesLocked = function() {
    1973   return this.lockedSet_;
    1974 };
    1975
    1976 /**
    1977  * Fires when there's data available to be graphed.
    1978  * @param {string} data Raw CSV data to be plotted
    1979  * @private
    1980  */
    1981 Dygraph.prototype.loadedEvent_ = function(data) {
    1982   this.rawData_ = this.parseCSV_(data);
    1983   this.cascadeDataDidUpdateEvent_();
    1984   this.predraw_();
    1985 };
    1986
    1987 /**
    1988  * Add ticks on the x-axis representing years, months, quarters, weeks, or days
    1989  * @private
    1990  */
    1991 Dygraph.prototype.addXTicks_ = function() {
    1992   // Determine the correct ticks scale on the x-axis: quarterly, monthly, ...
    1993   var range;
    1994   if (this.dateWindow_) {
    1995     range = [this.dateWindow_[0], this.dateWindow_[1]];
    1996   } else {
    1997     range = this.xAxisExtremes();
    1998   }
    1999
    2000   var xAxisOptionsView = this.optionsViewForAxis_('x');
    2001   var xTicks = xAxisOptionsView('ticker')(
    2002       range[0],
    2003       range[1],
    2004       this.plotter_.area.w,  // TODO(danvk): should be area.width
    2005       xAxisOptionsView,
    2006       this);
    2007   // var msg = 'ticker(' + range[0] + ', ' + range[1] + ', ' + this.width_ + ', ' + this.attr_('pixelsPerXLabel') + ') -> ' + JSON.stringify(xTicks);
    2008   // console.log(msg);
    2009   this.layout_.setXTicks(xTicks);
    2010 };
    2011
    2012 /**
    2013  * Returns the correct handler class for the currently set options.
    2014  * @private
    2015  */
    2016 Dygraph.prototype.getHandlerClass_ = function() {
    2017   var handlerClass;
    2018   if (this.attr_('dataHandler')) {
    2019     handlerClass =  this.attr_('dataHandler');
    2020   } else if (this.fractions_) {
    2021     if (this.getBooleanOption('errorBars')) {
    2022       handlerClass = FractionsBarsHandler;
    2023     } else {
    2024       handlerClass = DefaultFractionHandler;
    2025     }
    2026   } else if (this.getBooleanOption('customBars')) {
    2027     handlerClass = CustomBarsHandler;
    2028   } else if (this.getBooleanOption('errorBars')) {
    2029     handlerClass = ErrorBarsHandler;
    2030   } else {
    2031     handlerClass = DefaultHandler;
    2032   }
    2033   return handlerClass;
    2034 };
    2035
    2036 /**
    2037  * @private
    2038  * This function is called once when the chart's data is changed or the options
    2039  * dictionary is updated. It is _not_ called when the user pans or zooms. The
    2040  * idea is that values derived from the chart's data can be computed here,
    2041  * rather than every time the chart is drawn. This includes things like the
    2042  * number of axes, rolling averages, etc.
    2043  */
    2044 Dygraph.prototype.predraw_ = function() {
    2045   var start = new Date();
    2046
    2047   // Create the correct dataHandler
    2048   this.dataHandler_ = new (this.getHandlerClass_())();
    2049
    2050   this.layout_.computePlotArea();
    2051
    2052   // TODO(danvk): move more computations out of drawGraph_ and into here.
    2053   this.computeYAxes_();
    2054
    2055   if (!this.is_initial_draw_) {
    2056     this.canvas_ctx_.restore();
    2057     this.hidden_ctx_.restore();
    2058   }
    2059
    2060   this.canvas_ctx_.save();
    2061   this.hidden_ctx_.save();
    2062
    2063   // Create a new plotter.
    2064   this.plotter_ = new DygraphCanvasRenderer(this,
    2065                                             this.hidden_,
    2066                                             this.hidden_ctx_,
    2067                                             this.layout_);
    2068
    2069   // The roller sits in the bottom left corner of the chart. We don't know where
    2070   // this will be until the options are available, so it's positioned here.
    2071   this.createRollInterface_();
    2072
    2073   this.cascadeEvents_('predraw');
    2074
    2075   // Convert the raw data (a 2D array) into the internal format and compute
    2076   // rolling averages.
    2077   this.rolledSeries_ = [null];  // x-axis is the first series and it's special
    2078   for (var i = 1; i < this.numColumns(); i++) {
    2079     // var logScale = this.attr_('logscale', i); // TODO(klausw): this looks wrong // konigsberg thinks so too.
    2080     var series = this.dataHandler_.extractSeries(this.rawData_, i, this.attributes_);
    2081     if (this.rollPeriod_ > 1) {
    2082       series = this.dataHandler_.rollingAverage(series, this.rollPeriod_, this.attributes_, i);
    2083     }
    2084
    2085     this.rolledSeries_.push(series);
    2086   }
    2087
    2088   // If the data or options have changed, then we'd better redraw.
    2089   this.drawGraph_();
    2090
    2091   // This is used to determine whether to do various animations.
    2092   var end = new Date();
    2093   this.drawingTimeMs_ = (end - start);
    2094 };
    2095
    2096 /**
    2097  * Point structure.
    2098  *
    2099  * xval_* and yval_* are the original unscaled data values,
    2100  * while x_* and y_* are scaled to the range (0.0-1.0) for plotting.
    2101  * yval_stacked is the cumulative Y value used for stacking graphs,
    2102  * and bottom/top/minus/plus are used for high/low band graphs.
    2103  *
    2104  * @typedef {{
    2105  *     idx: number,
    2106  *     name: string,
    2107  *     x: ?number,
    2108  *     xval: ?number,
    2109  *     y_bottom: ?number,
    2110  *     y: ?number,
    2111  *     y_stacked: ?number,
    2112  *     y_top: ?number,
    2113  *     yval_minus: ?number,
    2114  *     yval: ?number,
    2115  *     yval_plus: ?number,
    2116  *     yval_stacked
    2117  * }}
    2118  */
    2119 Dygraph.PointType = undefined;
    2120
    2121 /**
    2122  * Calculates point stacking for stackedGraph=true.
    2123  *
    2124  * For stacking purposes, interpolate or extend neighboring data across
    2125  * NaN values based on stackedGraphNaNFill settings. This is for display
    2126  * only, the underlying data value as shown in the legend remains NaN.
    2127  *
    2128  * @param {Array.<Dygraph.PointType>} points Point array for a single series.
    2129  *     Updates each Point's yval_stacked property.
    2130  * @param {Array.<number>} cumulativeYval Accumulated top-of-graph stacked Y
    2131  *     values for the series seen so far. Index is the row number. Updated
    2132  *     based on the current series's values.
    2133  * @param {Array.<number>} seriesExtremes Min and max values, updated
    2134  *     to reflect the stacked values.
    2135  * @param {string} fillMethod Interpolation method, one of 'all', 'inside', or
    2136  *     'none'.
    2137  * @private
    2138  */
    2139 Dygraph.stackPoints_ = function(
    2140     points, cumulativeYval, seriesExtremes, fillMethod) {
    2141   var lastXval = null;
    2142   var prevPoint = null;
    2143   var nextPoint = null;
    2144   var nextPointIdx = -1;
    2145
    2146   // Find the next stackable point starting from the given index.
    2147   var updateNextPoint = function(idx) {
    2148     // If we've previously found a non-NaN point and haven't gone past it yet,
    2149     // just use that.
    2150     if (nextPointIdx >= idx) return;
    2151
    2152     // We haven't found a non-NaN point yet or have moved past it,
    2153     // look towards the right to find a non-NaN point.
    2154     for (var j = idx; j < points.length; ++j) {
    2155       // Clear out a previously-found point (if any) since it's no longer
    2156       // valid, we shouldn't use it for interpolation anymore.
    2157       nextPoint = null;
    2158       if (!isNaN(points[j].yval) && points[j].yval !== null) {
    2159         nextPointIdx = j;
    2160         nextPoint = points[j];
    2161         break;
    2162       }
    2163     }
    2164   };
    2165
    2166   for (var i = 0; i < points.length; ++i) {
    2167     var point = points[i];
    2168     var xval = point.xval;
    2169     if (cumulativeYval[xval] === undefined) {
    2170       cumulativeYval[xval] = 0;
    2171     }
    2172
    2173     var actualYval = point.yval;
    2174     if (isNaN(actualYval) || actualYval === null) {
    2175       if(fillMethod == 'none') {
    2176         actualYval = 0;
    2177       } else {
    2178         // Interpolate/extend for stacking purposes if possible.
    2179         updateNextPoint(i);
    2180         if (prevPoint && nextPoint && fillMethod != 'none') {
    2181           // Use linear interpolation between prevPoint and nextPoint.
    2182           actualYval = prevPoint.yval + (nextPoint.yval - prevPoint.yval) *
    2183               ((xval - prevPoint.xval) / (nextPoint.xval - prevPoint.xval));
    2184         } else if (prevPoint && fillMethod == 'all') {
    2185           actualYval = prevPoint.yval;
    2186         } else if (nextPoint && fillMethod == 'all') {
    2187           actualYval = nextPoint.yval;
    2188         } else {
    2189           actualYval = 0;
    2190         }
    2191       }
    2192     } else {
    2193       prevPoint = point;
    2194     }
    2195
    2196     var stackedYval = cumulativeYval[xval];
    2197     if (lastXval != xval) {
    2198       // If an x-value is repeated, we ignore the duplicates.
    2199       stackedYval += actualYval;
    2200       cumulativeYval[xval] = stackedYval;
    2201     }
    2202     lastXval = xval;
    2203
    2204     point.yval_stacked = stackedYval;
    2205
    2206     if (stackedYval > seriesExtremes[1]) {
    2207       seriesExtremes[1] = stackedYval;
    2208     }
    2209     if (stackedYval < seriesExtremes[0]) {
    2210       seriesExtremes[0] = stackedYval;
    2211     }
    2212   }
    2213 };
    2214
    2215 /**
    2216  * Loop over all fields and create datasets, calculating extreme y-values for
    2217  * each series and extreme x-indices as we go.
    2218  *
    2219  * dateWindow is passed in as an explicit parameter so that we can compute
    2220  * extreme values "speculatively", i.e. without actually setting state on the
    2221  * dygraph.
    2222  *
    2223  * @param {Array.<Array.<Array.<(number|Array<number>)>>} rolledSeries, where
    2224  *     rolledSeries[seriesIndex][row] = raw point, where
    2225  *     seriesIndex is the column number starting with 1, and
    2226  *     rawPoint is [x,y] or [x, [y, err]] or [x, [y, yminus, yplus]].
    2227  * @param {?Array.<number>} dateWindow [xmin, xmax] pair, or null.
    2228  * @return {{
    2229  *     points: Array.<Array.<Dygraph.PointType>>,
    2230  *     seriesExtremes: Array.<Array.<number>>,
    2231  *     boundaryIds: Array.<number>}}
    2232  * @private
    2233  */
    2234 Dygraph.prototype.gatherDatasets_ = function(rolledSeries, dateWindow) {
    2235   var boundaryIds = [];
    2236   var points = [];
    2237   var cumulativeYval = [];  // For stacked series.
    2238   var extremes = {};  // series name -> [low, high]
    2239   var seriesIdx, sampleIdx;
    2240   var firstIdx, lastIdx;
    2241   var axisIdx;
    2242
    2243   // Loop over the fields (series).  Go from the last to the first,
    2244   // because if they're stacked that's how we accumulate the values.
    2245   var num_series = rolledSeries.length - 1;
    2246   var series;
    2247   for (seriesIdx = num_series; seriesIdx >= 1; seriesIdx--) {
    2248     if (!this.visibility()[seriesIdx - 1]) continue;
    2249
    2250     // Prune down to the desired range, if necessary (for zooming)
    2251     // Because there can be lines going to points outside of the visible area,
    2252     // we actually prune to visible points, plus one on either side.
    2253     if (dateWindow) {
    2254       series = rolledSeries[seriesIdx];
    2255       var low = dateWindow[0];
    2256       var high = dateWindow[1];
    2257
    2258       // TODO(danvk): do binary search instead of linear search.
    2259       // TODO(danvk): pass firstIdx and lastIdx directly to the renderer.
    2260       firstIdx = null;
    2261       lastIdx = null;
    2262       for (sampleIdx = 0; sampleIdx < series.length; sampleIdx++) {
    2263         if (series[sampleIdx][0] >= low && firstIdx === null) {
    2264           firstIdx = sampleIdx;
    2265         }
    2266         if (series[sampleIdx][0] <= high) {
    2267           lastIdx = sampleIdx;
    2268         }
    2269       }
    2270
    2271       if (firstIdx === null) firstIdx = 0;
    2272       var correctedFirstIdx = firstIdx;
    2273       var isInvalidValue = true;
    2274       while (isInvalidValue && correctedFirstIdx > 0) {
    2275         correctedFirstIdx--;
    2276         // check if the y value is null.
    2277         isInvalidValue = series[correctedFirstIdx][1] === null;
    2278       }
    2279
    2280       if (lastIdx === null) lastIdx = series.length - 1;
    2281       var correctedLastIdx = lastIdx;
    2282       isInvalidValue = true;
    2283       while (isInvalidValue && correctedLastIdx < series.length - 1) {
    2284         correctedLastIdx++;
    2285         isInvalidValue = series[correctedLastIdx][1] === null;
    2286       }
    2287
    2288       if (correctedFirstIdx!==firstIdx) {
    2289         firstIdx = correctedFirstIdx;
    2290       }
    2291       if (correctedLastIdx !== lastIdx) {
    2292         lastIdx = correctedLastIdx;
    2293       }
    2294
    2295       boundaryIds[seriesIdx-1] = [firstIdx, lastIdx];
    2296
    2297       // .slice's end is exclusive, we want to include lastIdx.
    2298       series = series.slice(firstIdx, lastIdx + 1);
    2299     } else {
    2300       series = rolledSeries[seriesIdx];
    2301       boundaryIds[seriesIdx-1] = [0, series.length-1];
    2302     }
    2303
    2304     var seriesName = this.attr_("labels")[seriesIdx];
    2305     var seriesExtremes = this.dataHandler_.getExtremeYValues(series,
    2306         dateWindow, this.getBooleanOption("stepPlot", seriesName));
    2307
    2308     var seriesPoints = this.dataHandler_.seriesToPoints(series,
    2309         seriesName, boundaryIds[seriesIdx-1][0]);
    2310
    2311     if (this.getBooleanOption("stackedGraph")) {
    2312       axisIdx = this.attributes_.axisForSeries(seriesName);
    2313       if (cumulativeYval[axisIdx] === undefined) {
    2314         cumulativeYval[axisIdx] = [];
    2315       }
    2316       Dygraph.stackPoints_(seriesPoints, cumulativeYval[axisIdx], seriesExtremes,
    2317                            this.getBooleanOption("stackedGraphNaNFill"));
    2318     }
    2319
    2320     extremes[seriesName] = seriesExtremes;
    2321     points[seriesIdx] = seriesPoints;
    2322   }
    2323
    2324   return { points: points, extremes: extremes, boundaryIds: boundaryIds };
    2325 };
    2326
    2327 /**
    2328  * Update the graph with new data. This method is called when the viewing area
    2329  * has changed. If the underlying data or options have changed, predraw_ will
    2330  * be called before drawGraph_ is called.
    2331  *
    2332  * @private
    2333  */
    2334 Dygraph.prototype.drawGraph_ = function() {
    2335   var start = new Date();
    2336
    2337   // This is used to set the second parameter to drawCallback, below.
    2338   var is_initial_draw = this.is_initial_draw_;
    2339   this.is_initial_draw_ = false;
    2340
    2341   this.layout_.removeAllDatasets();
    2342   this.setColors_();
    2343   this.attrs_.pointSize = 0.5 * this.getNumericOption('highlightCircleSize');
    2344
    2345   var packed = this.gatherDatasets_(this.rolledSeries_, this.dateWindow_);
    2346   var points = packed.points;
    2347   var extremes = packed.extremes;
    2348   this.boundaryIds_ = packed.boundaryIds;
    2349
    2350   this.setIndexByName_ = {};
    2351   var labels = this.attr_("labels");
    2352   var dataIdx = 0;
    2353   for (var i = 1; i < points.length; i++) {
    2354     if (!this.visibility()[i - 1]) continue;
    2355     this.layout_.addDataset(labels[i], points[i]);
    2356     this.datasetIndex_[i] = dataIdx++;
    2357   }
    2358   for (var i = 0; i < labels.length; i++) {
    2359     this.setIndexByName_[labels[i]] = i;
    2360   }
    2361
    2362   this.computeYAxisRanges_(extremes);
    2363   this.layout_.setYAxes(this.axes_);
    2364
    2365   this.addXTicks_();
    2366
    2367   // Tell PlotKit to use this new data and render itself
    2368   this.layout_.evaluate();
    2369   this.renderGraph_(is_initial_draw);
    2370
    2371   if (this.getStringOption("timingName")) {
    2372     var end = new Date();
    2373     console.log(this.getStringOption("timingName") + " - drawGraph: " + (end - start) + "ms");
    2374   }
    2375 };
    2376
    2377 /**
    2378  * This does the work of drawing the chart. It assumes that the layout and axis
    2379  * scales have already been set (e.g. by predraw_).
    2380  *
    2381  * @private
    2382  */
    2383 Dygraph.prototype.renderGraph_ = function(is_initial_draw) {
    2384   this.cascadeEvents_('clearChart');
    2385   this.plotter_.clear();
    2386
    2387   const underlayCallback = this.getFunctionOption('underlayCallback');
    2388   if (underlayCallback) {
    2389     // NOTE: we pass the dygraph object to this callback twice to avoid breaking
    2390     // users who expect a deprecated form of this callback.
    2391     underlayCallback.call(this,
    2392         this.hidden_ctx_, this.layout_.getPlotArea(), this, this);
    2393   }
    2394
    2395   var e = {
    2396     canvas: this.hidden_,
    2397     drawingContext: this.hidden_ctx_
    2398   };
    2399   this.cascadeEvents_('willDrawChart', e);
    2400   this.plotter_.render();
    2401   this.cascadeEvents_('didDrawChart', e);
    2402   this.lastRow_ = -1;  // because plugins/legend.js clears the legend
    2403
    2404   // TODO(danvk): is this a performance bottleneck when panning?
    2405   // The interaction canvas should already be empty in that situation.
    2406   this.canvas_.getContext('2d').clearRect(0, 0, this.width_, this.height_);
    2407
    2408   const drawCallback = this.getFunctionOption("drawCallback");
    2409   if (drawCallback !== null) {
    2410     drawCallback.call(this, this, is_initial_draw);
    2411   }
    2412   if (is_initial_draw) {
    2413     this.readyFired_ = true;
    2414     while (this.readyFns_.length > 0) {
    2415       var fn = this.readyFns_.pop();
    2416       fn(this);
    2417     }
    2418   }
    2419 };
    2420
    2421 /**
    2422  * @private
    2423  * Determine properties of the y-axes which are independent of the data
    2424  * currently being displayed. This includes things like the number of axes and
    2425  * the style of the axes. It does not include the range of each axis and its
    2426  * tick marks.
    2427  * This fills in this.axes_.
    2428  * axes_ = [ { options } ]
    2429  *   indices are into the axes_ array.
    2430  */
    2431 Dygraph.prototype.computeYAxes_ = function() {
    2432   var axis, index, opts, v;
    2433
    2434   // this.axes_ doesn't match this.attributes_.axes_.options. It's used for
    2435   // data computation as well as options storage.
    2436   // Go through once and add all the axes.
    2437   this.axes_ = [];
    2438
    2439   for (axis = 0; axis < this.attributes_.numAxes(); axis++) {
    2440     // Add a new axis, making a copy of its per-axis options.
    2441     opts = { g : this };
    2442     utils.update(opts, this.attributes_.axisOptions(axis));
    2443     this.axes_[axis] = opts;
    2444   }
    2445
    2446   for (axis = 0; axis < this.axes_.length; axis++) {
    2447     if (axis === 0) {
    2448       opts = this.optionsViewForAxis_('y' + (axis ? '2' : ''));
    2449       v = opts("valueRange");
    2450       if (v) this.axes_[axis].valueRange = v;
    2451     } else {  // To keep old behavior
    2452       var axes = this.user_attrs_.axes;
    2453       if (axes && axes.y2) {
    2454         v = axes.y2.valueRange;
    2455         if (v) this.axes_[axis].valueRange = v;
    2456       }
    2457     }
    2458   }
    2459 };
    2460
    2461 /**
    2462  * Returns the number of y-axes on the chart.
    2463  * @return {number} the number of axes.
    2464  */
    2465 Dygraph.prototype.numAxes = function() {
    2466   return this.attributes_.numAxes();
    2467 };
    2468
    2469 /**
    2470  * @private
    2471  * Returns axis properties for the given series.
    2472  * @param {string} setName The name of the series for which to get axis
    2473  * properties, e.g. 'Y1'.
    2474  * @return {Object} The axis properties.
    2475  */
    2476 Dygraph.prototype.axisPropertiesForSeries = function(series) {
    2477   // TODO(danvk): handle errors.
    2478   return this.axes_[this.attributes_.axisForSeries(series)];
    2479 };
    2480
    2481 /**
    2482  * @private
    2483  * Determine the value range and tick marks for each axis.
    2484  * @param {Object} extremes A mapping from seriesName -> [low, high]
    2485  * This fills in the valueRange and ticks fields in each entry of this.axes_.
    2486  */
    2487 Dygraph.prototype.computeYAxisRanges_ = function(extremes) {
    2488   var isNullUndefinedOrNaN = function(num) {
    2489     return isNaN(parseFloat(num));
    2490   };
    2491   var numAxes = this.attributes_.numAxes();
    2492   var ypadCompat, span, series, ypad;
    2493
    2494   var p_axis;
    2495
    2496   // Compute extreme values, a span and tick marks for each axis.
    2497   for (var i = 0; i < numAxes; i++) {
    2498     var axis = this.axes_[i];
    2499     var logscale = this.attributes_.getForAxis("logscale", i);
    2500     var includeZero = this.attributes_.getForAxis("includeZero", i);
    2501     var independentTicks = this.attributes_.getForAxis("independentTicks", i);
    2502     series = this.attributes_.seriesForAxis(i);
    2503
    2504     // Add some padding. This supports two Y padding operation modes:
    2505     //
    2506     // - backwards compatible (yRangePad not set):
    2507     //   10% padding for automatic Y ranges, but not for user-supplied
    2508     //   ranges, and move a close-to-zero edge to zero, since drawing at the edge
    2509     //   results in invisible lines. Unfortunately lines drawn at the edge of a
    2510     //   user-supplied range will still be invisible. If logscale is
    2511     //   set, add a variable amount of padding at the top but
    2512     //   none at the bottom.
    2513     //
    2514     // - new-style (yRangePad set by the user):
    2515     //   always add the specified Y padding.
    2516     //
    2517     ypadCompat = true;
    2518     ypad = 0.1; // add 10%
    2519     const yRangePad = this.getNumericOption('yRangePad');
    2520     if (yRangePad !== null) {
    2521       ypadCompat = false;
    2522       // Convert pixel padding to ratio
    2523       ypad = yRangePad / this.plotter_.area.h;
    2524     }
    2525
    2526     if (series.length === 0) {
    2527       // If no series are defined or visible then use a reasonable default
    2528       axis.extremeRange = [0, 1];
    2529     } else {
    2530       // Calculate the extremes of extremes.
    2531       var minY = Infinity;  // extremes[series[0]][0];
    2532       var maxY = -Infinity;  // extremes[series[0]][1];
    2533       var extremeMinY, extremeMaxY;
    2534
    2535       for (var j = 0; j < series.length; j++) {
    2536         // this skips invisible series
    2537         if (!extremes.hasOwnProperty(series[j])) continue;
    2538
    2539         // Only use valid extremes to stop null data series' from corrupting the scale.
    2540         extremeMinY = extremes[series[j]][0];
    2541         if (extremeMinY !== null) {
    2542           minY = Math.min(extremeMinY, minY);
    2543         }
    2544         extremeMaxY = extremes[series[j]][1];
    2545         if (extremeMaxY !== null) {
    2546           maxY = Math.max(extremeMaxY, maxY);
    2547         }
    2548       }
    2549
    2550       // Include zero if requested by the user.
    2551       if (includeZero && !logscale) {
    2552         if (minY > 0) minY = 0;
    2553         if (maxY < 0) maxY = 0;
    2554       }
    2555
    2556       // Ensure we have a valid scale, otherwise default to [0, 1] for safety.
    2557       if (minY == Infinity) minY = 0;
    2558       if (maxY == -Infinity) maxY = 1;
    2559
    2560       span = maxY - minY;
    2561       // special case: if we have no sense of scale, center on the sole value.
    2562       if (span === 0) {
    2563         if (maxY !== 0) {
    2564           span = Math.abs(maxY);
    2565         } else {
    2566           // ... and if the sole value is zero, use range 0-1.
    2567           maxY = 1;
    2568           span = 1;
    2569         }
    2570       }
    2571
    2572       var maxAxisY = maxY, minAxisY = minY;
    2573       if (ypadCompat) {
    2574         if (logscale) {
    2575           maxAxisY = maxY + ypad * span;
    2576           minAxisY = minY;
    2577         } else {
    2578           maxAxisY = maxY + ypad * span;
    2579           minAxisY = minY - ypad * span;
    2580
    2581           // Backwards-compatible behavior: Move the span to start or end at zero if it's
    2582           // close to zero.
    2583           if (minAxisY < 0 && minY >= 0) minAxisY = 0;
    2584           if (maxAxisY > 0 && maxY <= 0) maxAxisY = 0;
    2585         }
    2586       }
    2587       axis.extremeRange = [minAxisY, maxAxisY];
    2588     }
    2589     if (axis.valueRange) {
    2590       // This is a user-set value range for this axis.
    2591       var y0 = isNullUndefinedOrNaN(axis.valueRange[0]) ? axis.extremeRange[0] : axis.valueRange[0];
    2592       var y1 = isNullUndefinedOrNaN(axis.valueRange[1]) ? axis.extremeRange[1] : axis.valueRange[1];
    2593       axis.computedValueRange = [y0, y1];
    2594     } else {
    2595       axis.computedValueRange = axis.extremeRange;
    2596     }
    2597     if (!ypadCompat) {
    2598       // When using yRangePad, adjust the upper/lower bounds to add
    2599       // padding unless the user has zoomed/panned the Y axis range.
    2600
    2601       y0 = axis.computedValueRange[0];
    2602       y1 = axis.computedValueRange[1];
    2603
    2604       // special case #781: if we have no sense of scale, center on the sole value.
    2605       if (y0 === y1) {
    2606         if(y0 === 0) {
    2607           y1 = 1;
    2608         } else {
    2609           var delta = Math.abs(y0 / 10);
    2610           y0 -= delta;
    2611           y1 += delta;
    2612         }
    2613       }
    2614
    2615       if (logscale) {
    2616         var y0pct = ypad / (2 * ypad - 1);
    2617         var y1pct = (ypad - 1) / (2 * ypad - 1);
    2618         axis.computedValueRange[0] = utils.logRangeFraction(y0, y1, y0pct);
    2619         axis.computedValueRange[1] = utils.logRangeFraction(y0, y1, y1pct);
    2620       } else {
    2621         span = y1 - y0;
    2622         axis.computedValueRange[0] = y0 - span * ypad;
    2623         axis.computedValueRange[1] = y1 + span * ypad;
    2624       }
    2625     }
    2626
    2627     if (independentTicks) {
    2628       axis.independentTicks = independentTicks;
    2629       var opts = this.optionsViewForAxis_('y' + (i ? '2' : ''));
    2630       var ticker = opts('ticker');
    2631       axis.ticks = ticker(axis.computedValueRange[0],
    2632               axis.computedValueRange[1],
    2633               this.plotter_.area.h,
    2634               opts,
    2635               this);
    2636       // Define the first independent axis as primary axis.
    2637       if (!p_axis) p_axis = axis;
    2638     }
    2639   }
    2640   if (p_axis === undefined) {
    2641     throw ("Configuration Error: At least one axis has to have the \"independentTicks\" option activated.");
    2642   }
    2643   // Add ticks. By default, all axes inherit the tick positions of the
    2644   // primary axis. However, if an axis is specifically marked as having
    2645   // independent ticks, then that is permissible as well.
    2646   for (var i = 0; i < numAxes; i++) {
    2647     var axis = this.axes_[i];
    2648
    2649     if (!axis.independentTicks) {
    2650       var opts = this.optionsViewForAxis_('y' + (i ? '2' : ''));
    2651       var ticker = opts('ticker');
    2652       var p_ticks = p_axis.ticks;
    2653       var p_scale = p_axis.computedValueRange[1] - p_axis.computedValueRange[0];
    2654       var scale = axis.computedValueRange[1] - axis.computedValueRange[0];
    2655       var tick_values = [];
    2656       for (var k = 0; k < p_ticks.length; k++) {
    2657         var y_frac = (p_ticks[k].v - p_axis.computedValueRange[0]) / p_scale;
    2658         var y_val = axis.computedValueRange[0] + y_frac * scale;
    2659         tick_values.push(y_val);
    2660       }
    2661
    2662       axis.ticks = ticker(axis.computedValueRange[0],
    2663                           axis.computedValueRange[1],
    2664                           this.plotter_.area.h,
    2665                           opts,
    2666                           this,
    2667                           tick_values);
    2668     }
    2669   }
    2670 };
    2671
    2672 /**
    2673  * Detects the type of the str (date or numeric) and sets the various
    2674  * formatting attributes in this.attrs_ based on this type.
    2675  * @param {string} str An x value.
    2676  * @private
    2677  */
    2678 Dygraph.prototype.detectTypeFromString_ = function(str) {
    2679   var isDate = false;
    2680   var dashPos = str.indexOf('-');  // could be 2006-01-01 _or_ 1.0e-2
    2681   if ((dashPos > 0 && (str[dashPos-1] != 'e' && str[dashPos-1] != 'E')) ||
    2682       str.indexOf('/') >= 0 ||
    2683       isNaN(parseFloat(str))) {
    2684     isDate = true;
    2685   }
    2686
    2687   this.setXAxisOptions_(isDate);
    2688 };
    2689
    2690 Dygraph.prototype.setXAxisOptions_ = function(isDate) {
    2691   if (isDate) {
    2692     this.attrs_.xValueParser = utils.dateParser;
    2693     this.attrs_.axes.x.valueFormatter = utils.dateValueFormatter;
    2694     this.attrs_.axes.x.ticker = DygraphTickers.dateTicker;
    2695     this.attrs_.axes.x.axisLabelFormatter = utils.dateAxisLabelFormatter;
    2696   } else {
    2697     /** @private (shut up, jsdoc!) */
    2698     this.attrs_.xValueParser = function(x) { return parseFloat(x); };
    2699     // TODO(danvk): use Dygraph.numberValueFormatter here?
    2700     /** @private (shut up, jsdoc!) */
    2701     this.attrs_.axes.x.valueFormatter = function(x) { return x; };
    2702     this.attrs_.axes.x.ticker = DygraphTickers.numericTicks;
    2703     this.attrs_.axes.x.axisLabelFormatter = this.attrs_.axes.x.valueFormatter;
    2704   }
    2705 };
    2706
    2707 /**
    2708  * @private
    2709  * Parses a string in a special csv format.  We expect a csv file where each
    2710  * line is a date point, and the first field in each line is the date string.
    2711  * We also expect that all remaining fields represent series.
    2712  * if the errorBars attribute is set, then interpret the fields as:
    2713  * date, series1, stddev1, series2, stddev2, ...
    2714  * @param {[Object]} data See above.
    2715  *
    2716  * @return [Object] An array with one entry for each row. These entries
    2717  * are an array of cells in that row. The first entry is the parsed x-value for
    2718  * the row. The second, third, etc. are the y-values. These can take on one of
    2719  * three forms, depending on the CSV and constructor parameters:
    2720  * 1. numeric value
    2721  * 2. [ value, stddev ]
    2722  * 3. [ low value, center value, high value ]
    2723  */
    2724 Dygraph.prototype.parseCSV_ = function(data) {
    2725   var ret = [];
    2726   var line_delimiter = utils.detectLineDelimiter(data);
    2727   var lines = data.split(line_delimiter || "\n");
    2728   var vals, j;
    2729
    2730   // Use the default delimiter or fall back to a tab if that makes sense.
    2731   var delim = this.getStringOption('delimiter');
    2732   if (lines[0].indexOf(delim) == -1 && lines[0].indexOf('\t') >= 0) {
    2733     delim = '\t';
    2734   }
    2735
    2736   var start = 0;
    2737   if (!('labels' in this.user_attrs_)) {
    2738     // User hasn't explicitly set labels, so they're (presumably) in the CSV.
    2739     start = 1;
    2740     this.attrs_.labels = lines[0].split(delim);  // NOTE: _not_ user_attrs_.
    2741     this.attributes_.reparseSeries();
    2742   }
    2743   var line_no = 0;
    2744
    2745   var xParser;
    2746   var defaultParserSet = false;  // attempt to auto-detect x value type
    2747   var expectedCols = this.attr_("labels").length;
    2748   var outOfOrder = false;
    2749   for (var i = start; i < lines.length; i++) {
    2750     var line = lines[i];
    2751     line_no = i;
    2752     if (line.length === 0) continue;  // skip blank lines
    2753     if (line[0] == '#') continue;    // skip comment lines
    2754     var inFields = line.split(delim);
    2755     if (inFields.length < 2) continue;
    2756
    2757     var fields = [];
    2758     if (!defaultParserSet) {
    2759       this.detectTypeFromString_(inFields[0]);
    2760       xParser = this.getFunctionOption("xValueParser");
    2761       defaultParserSet = true;
    2762     }
    2763     fields[0] = xParser(inFields[0], this);
    2764
    2765     // If fractions are expected, parse the numbers as "A/B"
    2766     if (this.fractions_) {
    2767       for (j = 1; j < inFields.length; j++) {
    2768         // TODO(danvk): figure out an appropriate way to flag parse errors.
    2769         vals = inFields[j].split("/");
    2770         if (vals.length != 2) {
    2771           console.error('Expected fractional "num/den" values in CSV data ' +
    2772                         "but found a value '" + inFields[j] + "' on line " +
    2773                         (1 + i) + " ('" + line + "') which is not of this form.");
    2774           fields[j] = [0, 0];
    2775         } else {
    2776           fields[j] = [utils.parseFloat_(vals[0], i, line),
    2777                        utils.parseFloat_(vals[1], i, line)];
    2778         }
    2779       }
    2780     } else if (this.getBooleanOption("errorBars")) {
    2781       // If there are sigma-based high/low bands, values are (value, stddev) pairs
    2782       if (inFields.length % 2 != 1) {
    2783         console.error('Expected alternating (value, stdev.) pairs in CSV data ' +
    2784                       'but line ' + (1 + i) + ' has an odd number of values (' +
    2785                       (inFields.length - 1) + "): '" + line + "'");
    2786       }
    2787       for (j = 1; j < inFields.length; j += 2) {
    2788         fields[(j + 1) / 2] = [utils.parseFloat_(inFields[j], i, line),
    2789                                utils.parseFloat_(inFields[j + 1], i, line)];
    2790       }
    2791     } else if (this.getBooleanOption("customBars")) {
    2792       // Custom high/low bands are a low;centre;high tuple
    2793       for (j = 1; j < inFields.length; j++) {
    2794         var val = inFields[j];
    2795         if (/^ *$/.test(val)) {
    2796           fields[j] = [null, null, null];
    2797         } else {
    2798           vals = val.split(";");
    2799           if (vals.length == 3) {
    2800             fields[j] = [ utils.parseFloat_(vals[0], i, line),
    2801                           utils.parseFloat_(vals[1], i, line),
    2802                           utils.parseFloat_(vals[2], i, line) ];
    2803           } else {
    2804             console.warn('When using customBars, values must be either blank ' +
    2805                          'or "low;center;high" tuples (got "' + val +
    2806                          '" on line ' + (1+i) + ')');
    2807           }
    2808         }
    2809       }
    2810     } else {
    2811       // Values are just numbers
    2812       for (j = 1; j < inFields.length; j++) {
    2813         fields[j] = utils.parseFloat_(inFields[j], i, line);
    2814       }
    2815     }
    2816     if (ret.length > 0 && fields[0] < ret[ret.length - 1][0]) {
    2817       outOfOrder = true;
    2818     }
    2819
    2820     if (fields.length != expectedCols) {
    2821       console.error("Number of columns in line " + i + " (" + fields.length +
    2822                     ") does not agree with number of labels (" + expectedCols +
    2823                     ") " + line);
    2824     }
    2825
    2826     // If the user specified the 'labels' option and none of the cells of the
    2827     // first row parsed correctly, then they probably double-specified the
    2828     // labels. We go with the values set in the option, discard this row and
    2829     // log a warning to the JS console.
    2830     if (i === 0 && this.attr_('labels')) {
    2831       var all_null = true;
    2832       for (j = 0; all_null && j < fields.length; j++) {
    2833         if (fields[j]) all_null = false;
    2834       }
    2835       if (all_null) {
    2836         console.warn("The dygraphs 'labels' option is set, but the first row " +
    2837                      "of CSV data ('" + line + "') appears to also contain " +
    2838                      "labels. Will drop the CSV labels and use the option " +
    2839                      "labels.");
    2840         continue;
    2841       }
    2842     }
    2843     ret.push(fields);
    2844   }
    2845
    2846   if (outOfOrder) {
    2847     console.warn("CSV is out of order; order it correctly to speed loading.");
    2848     ret.sort(function(a,b) { return a[0] - b[0]; });
    2849   }
    2850
    2851   return ret;
    2852 };
    2853
    2854 // In native format, all values must be dates or numbers.
    2855 // This check isn't perfect but will catch most mistaken uses of strings.
    2856 function validateNativeFormat(data) {
    2857   const firstRow = data[0];
    2858   const firstX = firstRow[0];
    2859   if (typeof firstX !== 'number' && !utils.isDateLike(firstX)) {
    2860     throw new Error(`Expected number or date but got ${typeof firstX}: ${firstX}.`);
    2861   }
    2862   for (let i = 1; i < firstRow.length; i++) {
    2863     const val = firstRow[i];
    2864     if (val === null || val === undefined) continue;
    2865     if (typeof val === 'number') continue;
    2866     if (utils.isArrayLike(val)) continue;  // e.g. errorBars or customBars
    2867     throw new Error(`Expected number or array but got ${typeof val}: ${val}.`);
    2868   }
    2869 }
    2870
    2871 /**
    2872  * The user has provided their data as a pre-packaged JS array. If the x values
    2873  * are numeric, this is the same as dygraphs' internal format. If the x values
    2874  * are dates, we need to convert them from Date objects to ms since epoch.
    2875  * @param {!Array} data
    2876  * @return {Object} data with numeric x values.
    2877  * @private
    2878  */
    2879 Dygraph.prototype.parseArray_ = function(data) {
    2880   // Peek at the first x value to see if it's numeric.
    2881   if (data.length === 0) {
    2882     data = [[0]];
    2883   }
    2884   if (data[0].length === 0) {
    2885     console.error("Data set cannot contain an empty row");
    2886     return null;
    2887   }
    2888
    2889   validateNativeFormat(data);
    2890
    2891   var i;
    2892   if (this.attr_("labels") === null) {
    2893     console.warn("Using default labels. Set labels explicitly via 'labels' " +
    2894                  "in the options parameter");
    2895     this.attrs_.labels = [ "X" ];
    2896     for (i = 1; i < data[0].length; i++) {
    2897       this.attrs_.labels.push("Y" + i); // Not user_attrs_.
    2898     }
    2899     this.attributes_.reparseSeries();
    2900   } else {
    2901     var num_labels = this.attr_("labels");
    2902     if (num_labels.length != data[0].length) {
    2903       console.error("Mismatch between number of labels (" + num_labels + ")" +
    2904                     " and number of columns in array (" + data[0].length + ")");
    2905       return null;
    2906     }
    2907   }
    2908
    2909   if (utils.isDateLike(data[0][0])) {
    2910     // Some intelligent defaults for a date x-axis.
    2911     this.attrs_.axes.x.valueFormatter = utils.dateValueFormatter;
    2912     this.attrs_.axes.x.ticker = DygraphTickers.dateTicker;
    2913     this.attrs_.axes.x.axisLabelFormatter = utils.dateAxisLabelFormatter;
    2914
    2915     // Assume they're all dates.
    2916     var parsedData = utils.clone(data);
    2917     for (i = 0; i < data.length; i++) {
    2918       if (parsedData[i].length === 0) {
    2919         console.error("Row " + (1 + i) + " of data is empty");
    2920         return null;
    2921       }
    2922       if (parsedData[i][0] === null ||
    2923           typeof(parsedData[i][0].getTime) != 'function' ||
    2924           isNaN(parsedData[i][0].getTime())) {
    2925         console.error("x value in row " + (1 + i) + " is not a Date");
    2926         return null;
    2927       }
    2928       parsedData[i][0] = parsedData[i][0].getTime();
    2929     }
    2930     return parsedData;
    2931   } else {
    2932     // Some intelligent defaults for a numeric x-axis.
    2933     /** @private (shut up, jsdoc!) */
    2934     this.attrs_.axes.x.valueFormatter = function(x) { return x; };
    2935     this.attrs_.axes.x.ticker = DygraphTickers.numericTicks;
    2936     this.attrs_.axes.x.axisLabelFormatter = utils.numberAxisLabelFormatter;
    2937     return data;
    2938   }
    2939 };
    2940
    2941 /**
    2942  * Parses a DataTable object from gviz.
    2943  * The data is expected to have a first column that is either a date or a
    2944  * number. All subsequent columns must be numbers. If there is a clear mismatch
    2945  * between this.xValueParser_ and the type of the first column, it will be
    2946  * fixed. Fills out rawData_.
    2947  * @param {!google.visualization.DataTable} data See above.
    2948  * @private
    2949  */
    2950 Dygraph.prototype.parseDataTable_ = function(data) {
    2951   var shortTextForAnnotationNum = function(num) {
    2952     // converts [0-9]+ [A-Z][a-z]*
    2953     // example: 0=A, 1=B, 25=Z, 26=Aa, 27=Ab
    2954     // and continues like.. Ba Bb .. Za .. Zz..Aaa...Zzz Aaaa Zzzz
    2955     var shortText = String.fromCharCode(65 /* A */ + num % 26);
    2956     num = Math.floor(num / 26);
    2957     while ( num > 0 ) {
    2958       shortText = String.fromCharCode(65 /* A */ + (num - 1) % 26 ) + shortText.toLowerCase();
    2959       num = Math.floor((num - 1) / 26);
    2960     }
    2961     return shortText;
    2962   };
    2963
    2964   var cols = data.getNumberOfColumns();
    2965   var rows = data.getNumberOfRows();
    2966
    2967   var indepType = data.getColumnType(0);
    2968   if (indepType == 'date' || indepType == 'datetime') {
    2969     this.attrs_.xValueParser = utils.dateParser;
    2970     this.attrs_.axes.x.valueFormatter = utils.dateValueFormatter;
    2971     this.attrs_.axes.x.ticker = DygraphTickers.dateTicker;
    2972     this.attrs_.axes.x.axisLabelFormatter = utils.dateAxisLabelFormatter;
    2973   } else if (indepType == 'number') {
    2974     this.attrs_.xValueParser = function(x) { return parseFloat(x); };
    2975     this.attrs_.axes.x.valueFormatter = function(x) { return x; };
    2976     this.attrs_.axes.x.ticker = DygraphTickers.numericTicks;
    2977     this.attrs_.axes.x.axisLabelFormatter = this.attrs_.axes.x.valueFormatter;
    2978   } else {
    2979     throw new Error(
    2980           "only 'date', 'datetime' and 'number' types are supported " +
    2981           "for column 1 of DataTable input (Got '" + indepType + "')");
    2982   }
    2983
    2984   // Array of the column indices which contain data (and not annotations).
    2985   var colIdx = [];
    2986   var annotationCols = {};  // data index -> [annotation cols]
    2987   var hasAnnotations = false;
    2988   var i, j;
    2989   for (i = 1; i < cols; i++) {
    2990     var type = data.getColumnType(i);
    2991     if (type == 'number') {
    2992       colIdx.push(i);
    2993     } else if (type == 'string' && this.getBooleanOption('displayAnnotations')) {
    2994       // This is OK -- it's an annotation column.
    2995       var dataIdx = colIdx[colIdx.length - 1];
    2996       if (!annotationCols.hasOwnProperty(dataIdx)) {
    2997         annotationCols[dataIdx] = [i];
    2998       } else {
    2999         annotationCols[dataIdx].push(i);
    3000       }
    3001       hasAnnotations = true;
    3002     } else {
    3003       throw new Error(
    3004           "Only 'number' is supported as a dependent type with Gviz." +
    3005           " 'string' is only supported if displayAnnotations is true");
    3006     }
    3007   }
    3008
    3009   // Read column labels
    3010   // TODO(danvk): add support back for errorBars
    3011   var labels = [data.getColumnLabel(0)];
    3012   for (i = 0; i < colIdx.length; i++) {
    3013     labels.push(data.getColumnLabel(colIdx[i]));
    3014     if (this.getBooleanOption("errorBars")) i += 1;
    3015   }
    3016   this.attrs_.labels = labels;
    3017   cols = labels.length;
    3018
    3019   var ret = [];
    3020   var outOfOrder = false;
    3021   var annotations = [];
    3022   for (i = 0; i < rows; i++) {
    3023     var row = [];
    3024     if (typeof(data.getValue(i, 0)) === 'undefined' ||
    3025         data.getValue(i, 0) === null) {
    3026       console.warn("Ignoring row " + i +
    3027                    " of DataTable because of undefined or null first column.");
    3028       continue;
    3029     }
    3030
    3031     if (indepType == 'date' || indepType == 'datetime') {
    3032       row.push(data.getValue(i, 0).getTime());
    3033     } else {
    3034       row.push(data.getValue(i, 0));
    3035     }
    3036     if (!this.getBooleanOption("errorBars")) {
    3037       for (j = 0; j < colIdx.length; j++) {
    3038         var col = colIdx[j];
    3039         row.push(data.getValue(i, col));
    3040         if (hasAnnotations &&
    3041             annotationCols.hasOwnProperty(col) &&
    3042             data.getValue(i, annotationCols[col][0]) !== null) {
    3043           var ann = {};
    3044           ann.series = data.getColumnLabel(col);
    3045           ann.xval = row[0];
    3046           ann.shortText = shortTextForAnnotationNum(annotations.length);
    3047           ann.text = '';
    3048           for (var k = 0; k < annotationCols[col].length; k++) {
    3049             if (k) ann.text += "\n";
    3050             ann.text += data.getValue(i, annotationCols[col][k]);
    3051           }
    3052           annotations.push(ann);
    3053         }
    3054       }
    3055
    3056       // Strip out infinities, which give dygraphs problems later on.
    3057       for (j = 0; j < row.length; j++) {
    3058         if (!isFinite(row[j])) row[j] = null;
    3059       }
    3060     } else {
    3061       for (j = 0; j < cols - 1; j++) {
    3062         row.push([ data.getValue(i, 1 + 2 * j), data.getValue(i, 2 + 2 * j) ]);
    3063       }
    3064     }
    3065     if (ret.length > 0 && row[0] < ret[ret.length - 1][0]) {
    3066       outOfOrder = true;
    3067     }
    3068     ret.push(row);
    3069   }
    3070
    3071   if (outOfOrder) {
    3072     console.warn("DataTable is out of order; order it correctly to speed loading.");
    3073     ret.sort(function(a,b) { return a[0] - b[0]; });
    3074   }
    3075   this.rawData_ = ret;
    3076
    3077   if (annotations.length > 0) {
    3078     this.setAnnotations(annotations, true);
    3079   }
    3080   this.attributes_.reparseSeries();
    3081 };
    3082
    3083 /**
    3084  * Signals to plugins that the chart data has updated.
    3085  * This happens after the data has updated but before the chart has redrawn.
    3086  * @private
    3087  */
    3088 Dygraph.prototype.cascadeDataDidUpdateEvent_ = function() {
    3089   // TODO(danvk): there are some issues checking xAxisRange() and using
    3090   // toDomCoords from handlers of this event. The visible range should be set
    3091   // when the chart is drawn, not derived from the data.
    3092   this.cascadeEvents_('dataDidUpdate', {});
    3093 };
    3094
    3095 /**
    3096  * Get the CSV data. If it's in a function, call that function. If it's in a
    3097  * file, do an XMLHttpRequest to get it.
    3098  * @private
    3099  */
    3100 Dygraph.prototype.start_ = function() {
    3101   var data = this.file_;
    3102
    3103   // Functions can return references of all other types.
    3104   if (typeof data == 'function') {
    3105     data = data();
    3106   }
    3107
    3108   const datatype = utils.typeArrayLike(data);
    3109   if (datatype == 'array') {
    3110     this.rawData_ = this.parseArray_(data);
    3111     this.cascadeDataDidUpdateEvent_();
    3112     this.predraw_();
    3113   } else if (datatype == 'object' &&
    3114              typeof data.getColumnRange == 'function') {
    3115     // must be a DataTable from gviz.
    3116     this.parseDataTable_(data);
    3117     this.cascadeDataDidUpdateEvent_();
    3118     this.predraw_();
    3119   } else if (datatype == 'string') {
    3120     // Heuristic: a newline means it's CSV data. Otherwise it's an URL.
    3121     var line_delimiter = utils.detectLineDelimiter(data);
    3122     if (line_delimiter) {
    3123       this.loadedEvent_(data);
    3124     } else {
    3125       // REMOVE_FOR_IE
    3126       var req;
    3127       if (window.XMLHttpRequest) {
    3128         // Firefox, Opera, IE7, and other browsers will use the native object
    3129         req = new XMLHttpRequest();
    3130       } else {
    3131         // IE 5 and 6 will use the ActiveX control
    3132         req = new ActiveXObject("Microsoft.XMLHTTP");
    3133       }
    3134
    3135       var caller = this;
    3136       req.onreadystatechange = function () {
    3137         if (req.readyState == 4) {
    3138           if (req.status === 200 ||  // Normal http
    3139               req.status === 0) {    // Chrome w/ --allow-file-access-from-files
    3140             caller.loadedEvent_(req.responseText);
    3141           }
    3142         }
    3143       };
    3144
    3145       req.open("GET", data, true);
    3146       req.send(null);
    3147     }
    3148   } else {
    3149     console.error("Unknown data format: " + datatype);
    3150   }
    3151 };
    3152
    3153 /**
    3154  * Changes various properties of the graph. These can include:
    3155  * <ul>
    3156  * <li>file: changes the source data for the graph</li>
    3157  * <li>errorBars: changes whether the data contains stddev</li>
    3158  * </ul>
    3159  *
    3160  * There's a huge variety of options that can be passed to this method. For a
    3161  * full list, see: https://dygraphs.com/options.html
    3162  *
    3163  * @param {Object} input_attrs The new properties and values
    3164  * @param {boolean} block_redraw Usually the chart is redrawn after every
    3165  *     call to updateOptions(). If you know better, you can pass true to
    3166  *     explicitly block the redraw. This can be useful for chaining
    3167  *     updateOptions() calls, avoiding the occasional infinite loop and
    3168  *     preventing redraws when it's not necessary (e.g. when updating a
    3169  *     callback).
    3170  */
    3171 Dygraph.prototype.updateOptions = function(input_attrs, block_redraw) {
    3172   if (typeof(block_redraw) == 'undefined') block_redraw = false;
    3173
    3174   // copyUserAttrs_ drops the "file" parameter as a convenience to us.
    3175   var file = input_attrs.file;
    3176   var attrs = Dygraph.copyUserAttrs_(input_attrs);
    3177   var prevNumAxes = this.attributes_.numAxes();
    3178
    3179   // TODO(danvk): this is a mess. Move these options into attr_.
    3180   if ('rollPeriod' in attrs) {
    3181     this.rollPeriod_ = attrs.rollPeriod;
    3182   }
    3183   if ('dateWindow' in attrs) {
    3184     this.dateWindow_ = attrs.dateWindow;
    3185   }
    3186
    3187   // TODO(danvk): validate per-series options.
    3188   // Supported:
    3189   // strokeWidth
    3190   // pointSize
    3191   // drawPoints
    3192   // highlightCircleSize
    3193
    3194   // Check if this set options will require new points.
    3195   var requiresNewPoints = utils.isPixelChangingOptionList(this.attr_("labels"), attrs);
    3196
    3197   utils.updateDeep(this.user_attrs_, attrs);
    3198
    3199   this.attributes_.reparseSeries();
    3200
    3201   if (prevNumAxes < this.attributes_.numAxes()) this.plotter_.clear();
    3202   if (file) {
    3203     // This event indicates that the data is about to change, but hasn't yet.
    3204     // TODO(danvk): support cancellation of the update via this event.
    3205     this.cascadeEvents_('dataWillUpdate', {});
    3206
    3207     this.file_ = file;
    3208     if (!block_redraw) this.start_();
    3209   } else {
    3210     if (!block_redraw) {
    3211       if (requiresNewPoints) {
    3212         this.predraw_();
    3213       } else {
    3214         this.renderGraph_(false);
    3215       }
    3216     }
    3217   }
    3218 };
    3219
    3220 /**
    3221  * Make a copy of input attributes, removing file as a convenience.
    3222  * @private
    3223  */
    3224 Dygraph.copyUserAttrs_ = function(attrs) {
    3225   var my_attrs = {};
    3226   for (var k in attrs) {
    3227     if (!attrs.hasOwnProperty(k)) continue;
    3228     if (k == 'file') continue;
    3229     if (attrs.hasOwnProperty(k)) my_attrs[k] = attrs[k];
    3230   }
    3231   return my_attrs;
    3232 };
    3233
    3234 /**
    3235  * Resizes the dygraph. If no parameters are specified, resizes to fill the
    3236  * containing div (which has presumably changed size since the dygraph was
    3237  * instantiated). If the width/height are specified, the div will be resized.
    3238  *
    3239  * This is far more efficient than destroying and re-instantiating a
    3240  * Dygraph, since it doesn't have to reparse the underlying data.
    3241  *
    3242  * @param {number} width Width (in pixels)
    3243  * @param {number} height Height (in pixels)
    3244  */
    3245 Dygraph.prototype.resize = function(width, height) {
    3246   if (this.resize_lock) {
    3247     return;
    3248   }
    3249   this.resize_lock = true;
    3250
    3251   if ((width === null) != (height === null)) {
    3252     console.warn("Dygraph.resize() should be called with zero parameters or " +
    3253                  "two non-NULL parameters. Pretending it was zero.");
    3254     width = height = null;
    3255   }
    3256
    3257   var old_width = this.width_;
    3258   var old_height = this.height_;
    3259
    3260   if (width) {
    3261     this.maindiv_.style.width = width + "px";
    3262     this.maindiv_.style.height = height + "px";
    3263     this.width_ = width;
    3264     this.height_ = height;
    3265   } else {
    3266     this.width_ = this.maindiv_.clientWidth;
    3267     this.height_ = this.maindiv_.clientHeight;
    3268   }
    3269
    3270   if (old_width != this.width_ || old_height != this.height_) {
    3271     // Resizing a canvas erases it, even when the size doesn't change, so
    3272     // any resize needs to be followed by a redraw.
    3273     this.resizeElements_();
    3274     this.predraw_();
    3275   }
    3276
    3277   this.resize_lock = false;
    3278 };
    3279
    3280 /**
    3281  * Adjusts the number of points in the rolling average. Updates the graph to
    3282  * reflect the new averaging period.
    3283  * @param {number} length Number of points over which to average the data.
    3284  */
    3285 Dygraph.prototype.adjustRoll = function(length) {
    3286   this.rollPeriod_ = length;
    3287   this.predraw_();
    3288 };
    3289
    3290 /**
    3291  * Returns a boolean array of visibility statuses.
    3292  */
    3293 Dygraph.prototype.visibility = function() {
    3294   // Do lazy-initialization, so that this happens after we know the number of
    3295   // data series.
    3296   if (!this.getOption("visibility")) {
    3297     this.attrs_.visibility = [];
    3298   }
    3299   // TODO(danvk): it looks like this could go into an infinite loop w/ user_attrs.
    3300   while (this.getOption("visibility").length < this.numColumns() - 1) {
    3301     this.attrs_.visibility.push(true);
    3302   }
    3303   return this.getOption("visibility");
    3304 };
    3305
    3306 /**
    3307  * Changes the visibility of one or more series.
    3308  *
    3309  * @param {number|number[]|object} num the series index or an array of series indices
    3310  *                                     or a boolean array of visibility states by index
    3311  *                                     or an object mapping series numbers, as keys, to
    3312  *                                     visibility state (boolean values)
    3313  * @param {boolean} value the visibility state expressed as a boolean
    3314  */
    3315 Dygraph.prototype.setVisibility = function(num, value) {
    3316   var x = this.visibility();
    3317   var numIsObject = false;
    3318
    3319   if (!Array.isArray(num)) {
    3320     if (num !== null && typeof num === 'object') {
    3321       numIsObject = true;
    3322     } else {
    3323       num = [num];
    3324     }
    3325   }
    3326
    3327   if (numIsObject) {
    3328     for (var i in num) {
    3329       if (num.hasOwnProperty(i)) {
    3330         if (i < 0 || i >= x.length) {
    3331           console.warn("Invalid series number in setVisibility: " + i);
    3332         } else {
    3333           x[i] = num[i];
    3334         }
    3335       }
    3336     }
    3337   } else {
    3338     for (var i = 0; i < num.length; i++) {
    3339       if (typeof num[i] === 'boolean') {
    3340         if (i >= x.length) {
    3341           console.warn("Invalid series number in setVisibility: " + i);
    3342         } else {
    3343           x[i] = num[i];
    3344         }
    3345       } else {
    3346         if (num[i] < 0 || num[i] >= x.length) {
    3347           console.warn("Invalid series number in setVisibility: " + num[i]);
    3348         } else {
    3349           x[num[i]] = value;
    3350         }
    3351       }
    3352     }
    3353   }
    3354
    3355   this.predraw_();
    3356 };
    3357
    3358 /**
    3359  * How large of an area will the dygraph render itself in?
    3360  * This is used for testing.
    3361  * @return A {width: w, height: h} object.
    3362  * @private
    3363  */
    3364 Dygraph.prototype.size = function() {
    3365   return { width: this.width_, height: this.height_ };
    3366 };
    3367
    3368 /**
    3369  * Update the list of annotations and redraw the chart.
    3370  * See dygraphs.com/annotations.html for more info on how to use annotations.
    3371  * @param ann {Array} An array of annotation objects.
    3372  * @param suppressDraw {Boolean} Set to "true" to block chart redraw (optional).
    3373  */
    3374 Dygraph.prototype.setAnnotations = function(ann, suppressDraw) {
    3375   // Only add the annotation CSS rule once we know it will be used.
    3376   this.annotations_ = ann;
    3377   if (!this.layout_) {
    3378     console.warn("Tried to setAnnotations before dygraph was ready. " +
    3379                  "Try setting them in a ready() block. See " +
    3380                  "dygraphs.com/tests/annotation.html");
    3381     return;
    3382   }
    3383
    3384   this.layout_.setAnnotations(this.annotations_);
    3385   if (!suppressDraw) {
    3386     this.predraw_();
    3387   }
    3388 };
    3389
    3390 /**
    3391  * Return the list of annotations.
    3392  */
    3393 Dygraph.prototype.annotations = function() {
    3394   return this.annotations_;
    3395 };
    3396
    3397 /**
    3398  * Get the list of label names for this graph. The first column is the
    3399  * x-axis, so the data series names start at index 1.
    3400  *
    3401  * Returns null when labels have not yet been defined.
    3402  */
    3403 Dygraph.prototype.getLabels = function() {
    3404   var labels = this.attr_("labels");
    3405   return labels ? labels.slice() : null;
    3406 };
    3407
    3408 /**
    3409  * Get the index of a series (column) given its name. The first column is the
    3410  * x-axis, so the data series start with index 1.
    3411  */
    3412 Dygraph.prototype.indexFromSetName = function(name) {
    3413   return this.setIndexByName_[name];
    3414 };
    3415
    3416 /**
    3417  * Find the row number corresponding to the given x-value.
    3418  * Returns null if there is no such x-value in the data.
    3419  * If there are multiple rows with the same x-value, this will return the
    3420  * first one.
    3421  * @param {number} xVal The x-value to look for (e.g. millis since epoch).
    3422  * @return {?number} The row number, which you can pass to getValue(), or null.
    3423  */
    3424 Dygraph.prototype.getRowForX = function(xVal) {
    3425   var low = 0,
    3426       high = this.numRows() - 1;
    3427
    3428   while (low <= high) {
    3429     var idx = (high + low) >> 1;
    3430     var x = this.getValue(idx, 0);
    3431     if (x < xVal) {
    3432       low = idx + 1;
    3433     } else if (x > xVal) {
    3434       high = idx - 1;
    3435     } else if (low != idx) {  // equal, but there may be an earlier match.
    3436       high = idx;
    3437     } else {
    3438       return idx;
    3439     }
    3440   }
    3441
    3442   return null;
    3443 };
    3444
    3445 /**
    3446  * Trigger a callback when the dygraph has drawn itself and is ready to be
    3447  * manipulated. This is primarily useful when dygraphs has to do an XHR for the
    3448  * data (i.e. a URL is passed as the data source) and the chart is drawn
    3449  * asynchronously. If the chart has already drawn, the callback will fire
    3450  * immediately.
    3451  *
    3452  * This is a good place to call setAnnotation().
    3453  *
    3454  * @param {function(!Dygraph)} callback The callback to trigger when the chart
    3455  *     is ready.
    3456  */
    3457 Dygraph.prototype.ready = function(callback) {
    3458   if (this.is_initial_draw_) {
    3459     this.readyFns_.push(callback);
    3460   } else {
    3461     callback.call(this, this);
    3462   }
    3463 };
    3464
    3465 /**
    3466  * Add an event handler. This event handler is kept until the graph is
    3467  * destroyed with a call to graph.destroy().
    3468  *
    3469  * @param {!Node} elem The element to add the event to.
    3470  * @param {string} type The type of the event, e.g. 'click' or 'mousemove'.
    3471  * @param {function(Event):(boolean|undefined)} fn The function to call
    3472  *     on the event. The function takes one parameter: the event object.
    3473  * @private
    3474  */
    3475 Dygraph.prototype.addAndTrackEvent = function(elem, type, fn) {
    3476   utils.addEvent(elem, type, fn);
    3477   this.registeredEvents_.push({elem, type, fn});
    3478 };
    3479
    3480 Dygraph.prototype.removeTrackedEvents_ = function() {
    3481   if (this.registeredEvents_) {
    3482     for (var idx = 0; idx < this.registeredEvents_.length; idx++) {
    3483       var reg = this.registeredEvents_[idx];
    3484       utils.removeEvent(reg.elem, reg.type, reg.fn);
    3485     }
    3486   }
    3487
    3488   this.registeredEvents_ = [];
    3489 };
    3490
    3491 // Installed plugins, in order of precedence (most-general to most-specific).
    3492 // This means that, in an event cascade, plugins which have registered
    3493 // for that event will be called in reverse order.
    3494 //
    3495 // This is most relevant for plugins which register a layout event,
    3496 // e.g. Axes, Legend and ChartLabels.
    3497 Dygraph.PLUGINS = [
    3498   LegendPlugin,
    3499   AxesPlugin,
    3500   RangeSelectorPlugin, // Has to be before ChartLabels so that its callbacks are called after ChartLabels' callbacks.
    3501   ChartLabelsPlugin,
    3502   AnnotationsPlugin,
    3503   GridPlugin
    3504 ];
    3505
    3506 // There are many symbols which have historically been available through the
    3507 // Dygraph class. These are exported here for backwards compatibility.
    3508 Dygraph.GVizChart = GVizChart;
    3509 Dygraph.DOTTED_LINE = utils.DOTTED_LINE;
    3510 Dygraph.DASHED_LINE = utils.DASHED_LINE;
    3511 Dygraph.DOT_DASH_LINE = utils.DOT_DASH_LINE;
    3512 Dygraph.dateAxisLabelFormatter = utils.dateAxisLabelFormatter;
    3513 Dygraph.toRGB_ = utils.toRGB_;
    3514 Dygraph.findPos = utils.findPos;
    3515 Dygraph.pageX = utils.pageX;
    3516 Dygraph.pageY = utils.pageY;
    3517 Dygraph.dateString_ = utils.dateString_;
    3518 Dygraph.defaultInteractionModel = DygraphInteraction.defaultModel;
    3519 Dygraph.nonInteractiveModel = Dygraph.nonInteractiveModel_ = DygraphInteraction.nonInteractiveModel_;
    3520 Dygraph.Circles = utils.Circles;
    3521
    3522 Dygraph.Plugins = {
    3523   Legend: LegendPlugin,
    3524   Axes: AxesPlugin,
    3525   Annotations: AnnotationsPlugin,
    3526   ChartLabels: ChartLabelsPlugin,
    3527   Grid: GridPlugin,
    3528   RangeSelector: RangeSelectorPlugin
    3529 };
    3530
    3531 Dygraph.DataHandlers = {
    3532   DefaultHandler,
    3533   BarsHandler,
    3534   CustomBarsHandler,
    3535   DefaultFractionHandler,
    3536   ErrorBarsHandler,
    3537   FractionsBarsHandler
    3538 };
    3539
    3540 Dygraph.startPan = DygraphInteraction.startPan;
    3541 Dygraph.startZoom = DygraphInteraction.startZoom;
    3542 Dygraph.movePan = DygraphInteraction.movePan;
    3543 Dygraph.moveZoom = DygraphInteraction.moveZoom;
    3544 Dygraph.endPan = DygraphInteraction.endPan;
    3545 Dygraph.endZoom = DygraphInteraction.endZoom;
    3546
    3547 Dygraph.numericLinearTicks = DygraphTickers.numericLinearTicks;
    3548 Dygraph.numericTicks = DygraphTickers.numericTicks;
    3549 Dygraph.integerTicks = DygraphTickers.integerTicks;
    3550 Dygraph.dateTicker = DygraphTickers.dateTicker;
    3551 Dygraph.Granularity = DygraphTickers.Granularity;
    3552 Dygraph.pickDateTickGranularity = DygraphTickers.pickDateTickGranularity;
    3553 Dygraph.getDateAxis = DygraphTickers.getDateAxis;
    3554 Dygraph.floatFormat = utils.floatFormat;
    3555
    3556 utils.setupDOMready_(Dygraph);
    3557
    3558 export default Dygraph;
    3559