Polar Plots

To switch to graphing with polar coordinates, type:

set polar

To switch back to Cartesian coordinates, type:

set nopolar

In polar mode, the independent variable x corresponds to the angle, or theta noramally used for polar plots. Polar plots are always plotted in a rectangular box, to change the size of the graph, use the set yrange command. This will change both the horizontal and vertical range. For an example, consider the following:

set polar
plot 3*cos(2*x)

To change the displayed range so their is extra space around the graph, type:

set yrange [-4:4]
replot

Note that this would leave the yrange set to [-4:4] for subsequent plots. To turn autoscaling back on, use the following:

set autoscale y

The default for interpretation of the angle is radians. To switch this value, you can use one of the following:

set angles degrees
set angles radians

3D Polar coordiantes

GnuPlot supports the 3D equivalent of polar coordinates, spherical and cylindrical coordinates, are only available for 3D data plots. For information on them, see help set mapping.

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