Fix spooky ValueError

axis.hexbin(...) raises this
ValueError: <matplotlib.colors.LinearSegmentedColormap object at 0x7fb752118550> is not a valid value for cmap

plotting/common.py

@@ -24,7 +24,7 @@ mpl.rcParams['axes.prop_cycle'] = mpl.cycler(color=petroff_colors)
 cmap_petroff_gradient = mpl.colors.LinearSegmentedColormap.from_list('Petroff gradient', [petroff_colors[i] for i in (9,0,4,2,6,1)])
 cmap_petroff_gradient.set_under(petroff_colors[3])
 cmap_petroff_gradient.set_over(petroff_colors[7])
-mpl.rcParams['image.cmap'] = cmap_petroff_gradient
+#mpl.rcParams['image.cmap'] = cmap_petroff_gradient
 
 cmap_petroff_bipolar = mpl.colors.LinearSegmentedColormap.from_list('Petroff bipolar', [petroff_colors[i] for i in (2,6,1,3,9,0,4)])
 cmap_petroff_bipolar.set_under(petroff_colors[5])