# xarray.CFTimeIndex

class `xarray.``CFTimeIndex`

  Custom Index for working with CF calendars and dates

  All elements of a CFTimeIndex must be cftime.datetime objects.

  Parameters:

  - data (array or CFTimeIndex) – Sequence of cftime.datetime objects to use in index
  - name (str, default None) – Name of the resulting index

  See also

  `cftime_range`

  `__init__`($self, /, *args, **kwargs)

    Initialize self. See help(type(self)) for accurate signature.

  Methods

  `all`(*args, **kwargs) | Return whether all elements are True.
  `any`(*args, **kwargs) | Return whether any element is True.
  `append`(other) | Append a collection of Index options together.
  `argmax`([axis, skipna]) | Return an ndarray of the maximum argument indexer.
  `argmin`([axis, skipna]) | Return a ndarray of the minimum argument indexer.
  `argsort`(*args, **kwargs) | Return the integer indices that would sort the index.
  `asof`(label) | Return the label from the index, or, if not present, the previous one.
  `asof_locs`(where, mask) | Find the locations (indices) of the labels from the index for every entry in the where argument.
  `astype`(dtype[, copy]) | Create an Index with values cast to dtypes.
  `contains`(key) | Needed for .loc based partial-string indexing
  `copy`([name, deep, dtype]) | Make a copy of this object.
  `delete`(loc) | Make new Index with passed location(-s) deleted.
  `difference`(other[, sort]) | Return a new Index with elements from the index that are not in other.
  `drop`(labels[, errors]) | Make new Index with passed list of labels deleted.
  `drop_duplicates`([keep]) | Return Index with duplicate values removed.
  `droplevel`([level]) | Return index with requested level(s) removed.
  `dropna`([how]) | Return Index without NA/NaN values
  `duplicated`([keep]) | Indicate duplicate index values.
  `equals`(other) | Determine if two Index objects contain the same elements.
  `factorize`([sort, na_sentinel]) | Encode the object as an enumerated type or categorical variable.
  `fillna`([value, downcast]) | Fill NA/NaN values with the specified value
  `format`([name, formatter]) | Render a string representation of the Index.
  `get_duplicates`() | Extract duplicated index elements.
  `get_indexer`(target[, method, limit, tolerance]) | Compute indexer and mask for new index given the current index.
  `get_indexer_for`(target, **kwargs) | Guaranteed return of an indexer even when non-unique.
  `get_indexer_non_unique`(target) | Compute indexer and mask for new index given the current index.
  `get_level_values`(level) | Return an Index of values for requested level.
  `get_loc`(key[, method, tolerance]) | Adapted from pandas.tseries.index.DatetimeIndex.get_loc
  `get_slice_bound`(label, side, kind) | Calculate slice bound that corresponds to given label.
  `get_value`(series, key) | Adapted from pandas.tseries.index.DatetimeIndex.get_value
  `get_values`() | Return Index data as an numpy.ndarray.
  `groupby`(values) | Group the index labels by a given array of values.
  `holds_integer`() | Whether the type is an integer type.
  `identical`(other) | Similar to equals, but check that other comparable attributes are also equal.
  `insert`(loc, item) | Make new Index inserting new item at location.
  `intersection`(other[, sort]) | Form the intersection of two Index objects.
  `is_`(other) | More flexible, faster check like `is` but that works through views.
  `is_boolean`() |
  `is_categorical`() | Check if the Index holds categorical data.
  `is_floating`() |
  `is_integer`() |
  `is_interval`() |
  `is_lexsorted_for_tuple`(tup) |
  `is_mixed`() |
  `is_numeric`() |
  `is_object`() |
  `is_type_compatible`(kind) | Whether the index type is compatible with the provided type.
  `isin`(values[, level]) | Return a boolean array where the index values are in values.
  `isna`() | Detect missing values.
  `isnull`() | Detect missing values.
  `item`() | Return the first element of the underlying data as a python scalar.
  `join`(other[, how, level, return_indexers, sort]) | Compute join_index and indexers to conform data structures to the new index.
  `map`(mapper[, na_action]) | Map values using input correspondence (a dict, Series, or function).
  `max`([axis, skipna]) | Return the maximum value of the Index.
  `memory_usage`([deep]) | Memory usage of the values
  `min`([axis, skipna]) | Return the minimum value of the Index.
  `notna`() | Detect existing (non-missing) values.
  `notnull`() | Detect existing (non-missing) values.
  `nunique`([dropna]) | Return number of unique elements in the object.
  `putmask`(mask, value) | Return a new Index of the values set with the mask.
  `ravel`([order]) | Return an ndarray of the flattened values of the underlying data.
  `reindex`(target[, method, level, limit, …]) | Create index with target’s values (move/add/delete values as necessary).
  `rename`(name[, inplace]) | Alter Index or MultiIndex name.
  `repeat`(repeats[, axis]) | Repeat elements of a Index.
  `searchsorted`(value[, side, sorter]) | Find indices where elements should be inserted to maintain order.
  `set_names`(names[, level, inplace]) | Set Index or MultiIndex name.
  `set_value`(arr, key, value) | Fast lookup of value from 1-dimensional ndarray.
  `shift`(n, freq) | Shift the CFTimeIndex a multiple of the given frequency.
  `slice_indexer`([start, end, step, kind]) | For an ordered or unique index, compute the slice indexer for input labels and step.
  `slice_locs`([start, end, step, kind]) | Compute slice locations for input labels.
  `sort`(*args, **kwargs) | Use sort_values instead.
  `sort_values`([return_indexer, ascending]) | Return a sorted copy of the index.
  `sortlevel`([level, ascending, sort_remaining]) | For internal compatibility with with the Index API.
  `strftime`(date_format) | Return an Index of formatted strings specified by date_format, which supports the same string format as the python standard library.
  `summary`([name]) | Return a summarized representation.
  `symmetric_difference`(other[, result_name, sort]) | Compute the symmetric difference of two Index objects.
  `take`(indices[, axis, allow_fill, fill_value]) | Return a new Index of the values selected by the indices.
  `to_datetimeindex`([unsafe]) | If possible, convert this index to a pandas.DatetimeIndex.
  `to_flat_index`() | Identity method.
  `to_frame`([index, name]) | Create a DataFrame with a column containing the Index.
  `to_list`() | Return a list of the values.
  `to_native_types`([slicer]) | Format specified values of self and return them.
  `to_numpy`([dtype, copy]) | A NumPy ndarray representing the values in this Series or Index.
  `to_series`([index, name]) | Create a Series with both index and values equal to the index keys useful with map for returning an indexer based on an index.
  `tolist`() | Return a list of the values.
  `transpose`(*args, **kwargs) | Return the transpose, which is by definition self.
  `union`(other[, sort]) | Form the union of two Index objects.
  `unique`([level]) | Return unique values in the index.
  `value_counts`([normalize, sort, ascending, …]) | Return a Series containing counts of unique values.
  `view`([cls]) |
  `where`(cond[, other]) | Return an Index of same shape as self and whose corresponding entries are from self where cond is True and otherwise are from other.

  Attributes

  `T` | Return the transpose, which is by definition self.
  `array` | The ExtensionArray of the data backing this Series or Index.
  `asi8` | Integer representation of the values.
  `base` | Return the base object if the memory of the underlying data is shared.
  `data` | Return the data pointer of the underlying data.
  `date_type` |
  `day` | The days of the datetime
  `dayofweek` | The day of week of the datetime
  `dayofyear` | The ordinal day of year of the datetime
  `dtype` | Return the dtype object of the underlying data.
  `dtype_str` | Return the dtype str of the underlying data.
  `empty` |
  `flags` | Return the ndarray.flags for the underlying data.
  `has_duplicates` |
  `hasnans` | Return if I have any nans; enables various perf speedups.
  `hour` | The hours of the datetime
  `inferred_type` | Return a string of the type inferred from the values.
  `is_all_dates` |
  `is_monotonic` | Alias for is_monotonic_increasing.
  `is_monotonic_decreasing` | Return if the index is monotonic decreasing (only equal or decreasing) values.
  `is_monotonic_increasing` | Return if the index is monotonic increasing (only equal or increasing) values.
  `is_unique` | Return if the index has unique values.
  `itemsize` | Return the size of the dtype of the item of the underlying data.
  `microsecond` | The microseconds of the datetime
  `minute` | The minutes of the datetime
  `month` | The month of the datetime
  `name` |
  `names` |
  `nbytes` | Return the number of bytes in the underlying data.
  `ndim` | Number of dimensions of the underlying data, by definition 1.
  `nlevels` | Number of levels.
  `second` | The seconds of the datetime
  `shape` | Return a tuple of the shape of the underlying data.
  `size` | Return the number of elements in the underlying data.
  `strides` | Return the strides of the underlying data.
  `values` | Return an array representing the data in the Index.
  `year` | The year of the datetime