From: John Hunter <jdhunter@ac...>  20040928 13:04:37

>>>>> "Dirk" == <replytodirk@...> writes: Dirk> I want to fill the area between two curves with a color Dirk> (incl. alpha channel, I use the agg backend). fill() seems Dirk> to fill only the area between the xaxis and one curve  at Dirk> least I found no way for filling only the area between two Dirk> graphs. Is there a way for doing so at all? Or do I have to Dirk> use another graphic library for this kind of fill_between()? All of the matplotlib plot commands create primitive objects (lines.Line2D, patches.Rectangle, patches.Polygon, text.Text). If a plot command doesn't suit your needs, you can roll your own by creating the right kind of primitive object. Here is a fill_between implementation from matplotlib.matlab import * from matplotlib.patches import Polygon def fill_between(ax, x, y1, y2, **kwargs): # add x,y2 in reverse order for proper polygon filling verts = zip(x,y1) + [(x[i], y2[i]) for i in range(len(x)1,1,1)] poly = Polygon(verts, **kwargs) ax.add_patch(poly) ax.autoscale_view() return poly x = arange(0, 2, 0.01) y1 = sin(2*pi*x) y2 = sin(4*pi*x) + 2 ax = gca() p = fill_between(ax, x, y1, y2, facecolor='g') p.set_alpha(0.5) show() Hope this helps, JDH 