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matplotlib : subplot with polar

Polar plots in matplotlib are generated using the polar(theta, R) command. The source for this command is simply (from the amazing '??' feature of IPython):

In [37]: m.polar??
Type: function
Base Class:
String Form:
Namespace: Interactive
File: c:\python25\lib\site-packages\matplotlib-0.91.2-py2.5-win32.egg\
matplotlib\pyplot.py
Definition: m.polar(*args, **kwargs)
Source:
def polar(*args, **kwargs):
"""
POLAR(theta, r)

Make a polar plot. Multiple theta, r arguments are supported,
with format strings, as in plot.
"""
ax = gca(polar=True)
ret = ax.plot(*args, **kwargs)
draw_if_interactive()
return ret

In order to make a subplot polar we simply add the polar=True argument thus:
m.subplot(nrows, ncols, nsubfig, polar=True)

Otherwise, it is treated as a cartesian plot even if you do m.polar(..) afterwards.
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Comments

  1. AnonymousDecember 20, 2010 at 1:00 AM

    Nice post, by far the most informative and concise example of how to plot a polar subplot I've found.

    ReplyDelete

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