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(gnuplot.info)polar

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Enter node , (file) or (file)node

 The `set polar` command changes the meaning of the plot from rectangular
 coordinates to polar coordinates.

 Syntax:
       set polar
       set nopolar
       show polar

 There have been changes made to polar mode in version 3.7, so that scripts
 for `gnuplot` (Note: gnuplot ) versions 3.5 and earlier will require
 modification.  The main change is that the dummy variable t is used for the
 angle so that the x and y ranges can be controlled independently.  Other
 changes are: 1) tics are no longer put along the zero axes automatically
 ---use `set xtics axis nomirror`; `set ytics axis nomirror`; 2) the grid, if
 selected, is not automatically polar ---use `set grid polar`; 3) the grid is
 not labelled with angles ---use `set label` (Note: label ) as necessary.

 In polar coordinates, the dummy variable (t) is an angle.  The default range
 of t is [0:2*pi], or, if degree units have been selected, to [0:360] (see
 `set angles` (Note: angles )).

 The command `set nopolar` changes the meaning of the plot back to the default
 rectangular coordinate system.

 The `set polar` command is not supported for `splot`s (Note: splot ).  See
 the  `set mapping` (Note: mapping ) command for similar functionality for
 `splot`s.

 While in polar coordinates the meaning of an expression in t is really
 r = f(t), where t is an angle of rotation.  The trange controls the domain
 (the angle) of the function, and the x and y ranges control the range of the
 graph in the x and y directions.  Each of these ranges, as well as the
 rrange, may be autoscaled or set explicitly.  See `set xrange`
 (Note: xrange ) for details of all the `set range` commands.

 Example:
       set polar
       plot t*sin(t)
       plot [-2*pi:2*pi] [-3:3] [-3:3] t*sin(t)

 The first `plot` (Note: plot ) uses the default polar angular domain of 0 to
 2*pi.  The radius and the size of the graph are scaled automatically.  The
 second `plot` expands the domain, and restricts the size of the graph to
 [-3:3] in both directions.

 You may want to `set size square` to have `gnuplot` try to make the aspect
 ratio equal to unity, so that circles look circular.