https://matplotlib.svn.sourceforge.net/svnroot/matplotlib/branches/v1_0_maint
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r8931 | weathergod | 2011-01-21 15:42:45 -0600 (Fri, 21 Jan 2011) | 3 lines
Fixes colors normalization with 'under' colors in LinearSegmentedColormap (values between -1 and 0 were being made positive due to an int cast).
Thanks to Eoghan Harrington for discovering and supplying the patch!
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