### 3.27 splot

‘splot‘ is the command for drawing 3D plots (well, actually projections on a 2D surface, but you knew that). It can create a plot from functions or data read from files in a manner very similar to the ‘plot‘ command. ‘splot‘ provides only a single x, y, and z axis; there is no equivalent to the x2 and y2 secondary axes provided by ‘plot‘.

See the ‘plot‘ command for many options available in both 2D and 3D plots.

Syntax:

          splot {<ranges>}
                {<iteration>}
                <function> | "<datafile>" {datafile-modifiers}}
                {<title-spec>} {with <style>}
                {, {definitions{,}} <function> ...}

where either a <function> or the name of a data file enclosed in quotes is supplied. The function can be a mathematical expression, or a triple of mathematical expressions in parametric mode.

By default ‘splot‘ draws the xy plane completely below the plotted data. The offset between the lowest ztic and the xy plane can be changed by xyplane. The orientation of a ‘splot‘ projection is controlled by view. See view and xyplane for more information.

The syntax for setting ranges on the ‘splot‘ command is the same as for ‘plot‘. In non-parametric mode, the order in which ranges must be given is xrange, yrange, and zrange. In parametric mode, the order is urange, vrange, xrange, yrange, and zrange.

The title option is the same as in ‘plot‘. The operation of with is also the same as in ‘plot‘, except that the plotting styles available to ‘splot‘ are limited to ‘lines‘, ‘points‘, linespoints, dots, and impulses; the error-bar capabilities of ‘plot‘ are not available for ‘splot‘.

The datafile options have more differences.

See also ‘show plot‘.