[matplotlib-devel] Color Parsing Bug

[T J <tj...@gm...>]

There seems to be an issue with how arguments are parsed when it comes
to determining the color of a line.  Generally, it seems that 'c'
takes precedence over 'color'. However, this precedence seems to
change with the number of passed kwargs.

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import matplotlib.pyplot as plt
import numpy as np

# 'c' seems to have precedence over 'color'
plt.plot(np.arange(10)-2, c='b', color='r') # line is blue
plt.plot(np.arange(10)-1, color='r', c='b') # line is blue

# But...
x = {'c': 'b',
 'color': 'r',
 'label': 'blah',
 'linestyle': '-',
 'linewidth': 3,
 'marker': None}

# Some strange parsing error
plt.plot(np.arange(10)+1, **x)  # line is red
del x['marker']  # delete any key but 'c' or 'color'
plt.plot(np.arange(10)+2, **x)  # line is blue
x['zorder'] = 3  # add back any key
plt.plot(np.arange(10)+3, **x)  # line is red

plt.show()