On Tue, Feb 1, 2011 at 1:11 PM, Benjamin Root <ben.r...@ou.edu> wrote: > > > On Tue, Feb 1, 2011 at 1:48 PM, Jeremy Conlin <jlcon...@gmail.com> wrote: >> >> On Tue, Feb 1, 2011 at 11:22 AM, Benjamin Root <ben.r...@ou.edu> wrote: >> > >> > >> > On Tue, Feb 1, 2011 at 11:58 AM, Jeremy Conlin <jlcon...@gmail.com> >> > wrote: >> >> >> >> I have two arrays and I want to plot the ratio of A/B when A>=B or B/A >> >> when A<B. I can create numpy masked arrays to find the result in >> >> these two instances, but I'm having trouble plotting them. Below I >> >> have a minimal example. I get a plot, but only from the second time I >> >> issue the pcolormesh command. Is there a way to combine the two >> >> arrays for plotting or to plot without overlapping? >> >> >> >> Thanks, >> >> Jeremy >> >> >> >> >> > >> > Try this: >> > >> > ratio = numpy.where(A >= B, A/B, B/A) >> > Figure = pyplot.figure() >> > pyplot.pcolormesh(ratio) >> > >> > I hope that helps! >> >> numpy.where helps a lot. To further complicate things, some elements >> of A or B are zero which causes A/B or B/A to be infinite in some >> places. I can use numpy.where or create a masked array to elimnate >> those elements that are infinite, but then my plotted values are >> either 0 or 1 (False or True); I lose all the interesting data. The >> documents of pcolormesh show that I can pass a masked_array, but I'm >> successful in doing that. Do you have another trick you can show to >> help me get around this problem? >> >> Thanks again, >> Jeremy > > > I think you are using the masked array and/or the np.where incorrectly. > > ratio = np.where(A >= B, A/B, B/A) > ratio = np.ma.masked_array(ratio, mask=(~np.isfinite(ratio))) > > And then do a contourf on ratio.
Yeah, that seems to work. Thanks for the help. Jeremy ------------------------------------------------------------------------------ Special Offer-- Download ArcSight Logger for FREE (a $49 USD value)! Finally, a world-class log management solution at an even better price-free! Download using promo code Free_Logger_4_Dev2Dev. Offer expires February 28th, so secure your free ArcSight Logger TODAY! http://p.sf.net/sfu/arcsight-sfd2d _______________________________________________ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
