On Jul 13, 4:47 pm, Jason Grout <jason-s...@creativetrax.com> wrote: > On 7/13/10 4:46 AM, David Sanders wrote: > > > > > Hi, > > > I need to superimpose several region_plot's. These have regions > > colored in different colors which may or may not overlap. However, if > > I do something like > > > var('p q') > > plot1 = region_plot([p+q<1, p+q>-1], (p,-2,2), (q,-2,2), incol='red') > > plot2 = region_plot([p-q<1, p-q>-1], (p,-2,2), (q,-2,2), incol='blue') > > show(plot1+plot2) > > > then I see at most the outline of the first plot. It seems that the > > second plot covers up the first plot, since the default value of > > outcol is 'white'. > > > Is there any way to make these plots transparent (i.e. with an alpha > > value less than 1), or at least not opaque? I tried putting the > > option > > > outcol=None > > > but this is not accepted. This would seem to me to be the first way of > > solving the issue. > > > I had a look at the code for region_plot, which I at least understand > > the idea of. It uses matplotlib for the graphics, so perhaps the > > question of transparency is a matplotlib question. Nonetheless, I > > believe that matplotlib does have this capability, so this should be > > possible...! > > It seems that adding transparency is a natural way to do this. I've > posted a rough patch to do this up > athttp://trac.sagemath.org/sage_trac/ticket/9491 > > I've also attached a figure resulting from: > > var('p q') > plot1 = region_plot([p+q<1, p+q>-1], (p,-2,2), (q,-2,2), incol='red', > opacity=0.5) > plot2 = region_plot([p-q<1, p-q>-1], (p,-2,2), (q,-2,2), incol='blue', > opacity=0.5) > show(plot1+plot2)
Exactly what I had in mind, thanks! David. > > Sorry I don't have right now to finish the patch and ask for review; I'm > rushing out the door. > > Thanks, > > Jason > > regionplot.png > 27KViewDownload -- To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URL: http://www.sagemath.org