From: John Hunter <jdhunter@ac...>  20040528 16:02:15

>>>>> "James" == James Boyle <boyle5@...> writes: James> Until contouring is implemented, the only way to display 2D James> data is by pcolor. I have two observations: James> (1) While trying to figure out exactly what pcolor was James> doing ( I did not understand the grid registration) I James> looked into the matlab documentation. The matlab docs James> explained what was going on, so that I could get my values James> properly aligned on the grid. This brings up a question  James> How close does matplotlib follow Matlab? Will there always James> be such a close correspondence in the implementation of James> functions such as I found in pcolor? The matlab interface tries to follow matlab pretty closely, but not religiously. For example, in matlab you can say plot(x,Y) where Y is MxN and it will plot all the data in the array. matplotlib doesn't handle this case, currently. In the case of errorbar, it made more sense to extend the features (eg to support x and y asymmetric errorbars) than slavishly follow the matlab signature. All other things being equal I try and implement the matlab signature. It's usually a good motivator because it encourages you to add features at design time that you might be tempted to leave out. Why do you ask? James> (2) To do quantitative representation using pcolor, a James> colorbar function is needed. This feature does not appear James> on the list of future goals, I would like it to be James> added. I'm not that competent, but I will give it a try James> myself. The first few easy things I tried did not work out. Agreed. I just implemented this. Unzip the following in your sitepackages dir http://nitace.bsd.uchicago.edu:8080/files/share/matplotlib.py0.54.2a.zip After you have created a pcolor, just do colorbar() This will resize your axes to make room for the colorbar and display a vertical colorbar (I haven't yet supported horizontal colorbars, as matlab does). If you want to use nondefault limits for the colormap, call cmap.set_clim(cmin, cmax) before the pcolor and colorbar, as in this example cmap = ColormapJet(256) cmap.set_clim(cmin, cmax) pcolor(Z, cmap=cmap) colorbar() Let me know how it goes! JDH 