colors: avoid problems with bad values under the mask when color mapping

efiring · efiring · commit 8c582e47f3d5 · 2012-08-06T11:16:01.000-10:00
This change should have no effect on any plot, but it avoids
warnings that can arise when an inf occurs under a mask.
diff --git a/lib/matplotlib/colors.py b/lib/matplotlib/colors.py
@@ -510,11 +510,10 @@ def __call__(self, X, alpha=None, bytes=False):
             xa = np.array([X])
         else:
             vtype = 'array'
-            xma = ma.array(X, copy=False)
-            mask_bad = xma.mask
-            xa = xma.data.copy()   # Copy here to avoid side effects.
+            xma = ma.array(X, copy=True)  # Copy here to avoid side effects.
+            mask_bad = xma.mask           # Mask will be used below.
+            xa = xma.filled()             # Fill to avoid infs, etc.
             del xma
-            # masked values are substituted below; no need to fill them here
 
         if xa.dtype.char in np.typecodes['Float']:
             # Treat 1.0 as slightly less than 1.
