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Here is the latest incarnation of HeatMapper. When I installed Snow Leopard almost two months ago the previous version, written using PyObjC, didn't work any more. I took Bill Bumgarner's advice and have been practicing to speak Cocoa and Objective-C since then.
The app makes heat maps, such as what you might find in R. It has an inspector window that allows customization of colors. The standard ones:
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Here are topo colors:
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For reasons that escape me, it was not written as a document-based application. But it does allow saving of UserPrefs. It also has some stuff that is probably only useful to me. It will color the row names according to a dictionary, but I haven't yet generalized this to allow the User to specify her/his own values. It can load csv data from a file.
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This is the app I think is most functional and I would really appreciate any feedback. As before, the source and the app (64-bit for Snow Leopard) is on my download page hosted at .mac. If you want a different build, or whatever, just let me know. You can get a hold of me here.
[UPDATE: The app seems broken (1.4 years later). That says more about my lack of comprehensive testing than anything else, I guess. Sorry. There is a link in comments about how to use R for this purpose, and I've posted about it too. For my part, now that I have matplotlib, I use that now. When I get time I'll look into this. ]