James Conners wrote: > Hi, > > I'm having some trouble producing a filled contour how I want it. > > Say I'm plotting data over the range [1.2, 20] using 15 level lines evenly > spaced > over that interval. I'd like the min of that interval to map to the min of > the color spectrum (say "jet" so dark blue) > and the max of that interval to map to the max of the spectrum (so red). It > doesn't seem to work that way. > When I do filled contours, sometimes the low values are mapped to black or > dark gray and > sometimes they're mapped to blue. > > I always want the endpoints of the spectrum to map to the endpoints of the > plotted values. Can this be done? > Any help is appreciated. Thanks.
The root of the problem is a questionable choice I made in the _process_colors method of ContourSet; I will investigate either changing it, or making it an option. In the meantime, there is an easy workaround: just use the set_clim method of the ContourSet, or the pyplot.clim function. In ipython -pylab: z = rand(10,10) cs = contourf(z) cb = colorbar() cs.set_clim(cs.layers.min(), cs.layers.max()) draw() The idea behind the present default choice for clim within contourf is that the range of colors covers values from the lowest contour level to the highest; the color of a *layer* is then the color of the midpoint between its bounding levels. This has some logic to it (and is more consistent with pcolor and image color mapping), but I agree that it probably makes more sense to use the full color range by default; most often, this is likely to be what one wants, and for the exceptions one can always use set_clim. Eric > > - James > > > ------------------------------------------------------------------------------ > The Planet: dedicated and managed hosting, cloud storage, colocation > Stay online with enterprise data centers and the best network in the business > Choose flexible plans and management services without long-term contracts > Personal 24x7 support from experience hosting pros just a phone call away. > http://p.sf.net/sfu/theplanet-com > _______________________________________________ > Matplotlib-users mailing list > Matplotlib-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/matplotlib-users ------------------------------------------------------------------------------ The Planet: dedicated and managed hosting, cloud storage, colocation Stay online with enterprise data centers and the best network in the business Choose flexible plans and management services without long-term contracts Personal 24x7 support from experience hosting pros just a phone call away. http://p.sf.net/sfu/theplanet-com _______________________________________________ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
