So for anyone out there who has been having pcolor'ing masked arrays in matplotlib, such that the masked regions are actually black, I found the fix
here (check the comments).
Apparently this has been fixed in the upstream versions, but it hasn't been sent down to the latest version of matplotlib packaged with ubuntu (I'm using karmic).
Basically, the fix goes like this:
Change line 491 in /usr/share/pyshared/matplotlib/colors.py from:
self._lut[:,-1] = alpha
to:
self._lut[:-1,-1] = alpha
Upon restarting python, pcolormesh should work properly.
For some reason the above link was rather difficult to find, so I thought I'd bump it.
