[matplotlib-devel] PATCH: Accept color/alpha in imsave

[Jostein Bø F. <jos...@gm...>]

I've had problems saving MxNx3 (RGB) numpy arrays as images using
imsave. It fails with an exception, and the problem seems to be line
1243 in image.py:

figsize = [x / float(dpi) for x in arr.shape[::-1]]

The purpose of arr.shape[::-1] seems to be to reorder the height and
width dimensions. It works as intended for MxN arrays, but not NxMx3
arrays -- they cause a function to complain about an argument too
many.

I have modified the above line to use (arr.shape[1], arr.shape[0])
instead of arr.shape[::-1], and that solves the problem for me, and I
get the output I expect (and the code still passes all tests it should
pass). However, there could very well be subtleties in the codebase
that I don't know about.

The attached patches add a simple test case, the above mentioned
change and a few updates to the documentation of imsave.

Best,

Jostein.