Hi,

I'm trying to fade some data, using alpha values, that I am plotting with Axes.plot().  I can recreate this problem with 1 line of pylab.plot.  If I use

pylab.plot([1,2,3],[1,4,9], color=(1,0,0,.2), linewidth=7)

then I get the equivalent of

pylab.plot([1,2,3],[1,4,9], color=(1,0,0), linewidth=7)

i.e. it does not use the alpha value.  However, if instead I use

pylab.plot([1,2,3],[1,4,9], color=(1,0,0), linewidth=7, alpha=.2)

then the line is faded out appropriately.  The plot documentation indicates that RGBA tuples should be valid, so I'm wondering if this is a bug.  Maybe alpha is defaulting to 1 or None and then not being overwritten if color is a 4-tuple?

I'm using Arch Linux with kernel 2.6.39, matplotlib 1.0.1 from the Arch repo, and the Qt4 backend.  My installed Qt version is 4.7.3, and I am using KDE 4.6.5.  Below is verbose-debug output.  Thanks for any help!

Ben


$HOME=/home/ben
CONFIGDIR=/home/ben/.matplotlib
matplotlib data path /usr/lib/python2.7/site-packages/matplotlib/mpl-data
loaded rc file /usr/lib/python2.7/site-packages/matplotlib/mpl-data/matplotlibrc
matplotlib version 1.0.1
verbose.level debug
interactive is False
units is False
platform is linux2
loaded modules: ['heapq', 'numpy.core.info', 'distutils', 'numpy.lib.format', 'functools', 'pylab', '_bisect', 'subprocess', 'sysconfig', 'gc', 'matplotlib.tempfile', 'distutils.sysconfig', 'ctypes._endian', 'encodings.encodings', 'pyparsing', 'matplotlib.colors', 'numpy.core.numerictypes', 'numpy.testing.sys', 'numpy.lib.__future__', 'numpy.fft.types', 'numpy.ma.cPickle', 'struct', 'numpy.matrixlib.defmatrix', 'numpy.random.info', 'tempfile', 'numpy.compat.types', 'pprint', 'numpy.linalg', 'matplotlib.threading', 'numpy.core.machar', 'numpy.testing.types', 'numpy.testing', 'collections', 'numpy.polynomial.sys', 'unittest.sys', 'numpy.core.umath', 'unittest.main', 'distutils.types', 'numpy.testing.operator', 'numpy.core.scalarmath', 'numpy.ma.sys', 'zipimport', 'string', 'matplotlib.subprocess', 'numpy.testing.os', 'unittest.functools', 'numpy.lib.arraysetops', 'numpy.testing.unittest', 'numpy.lib.math', 'encodings.utf_8', 'matplotlib.__future__', 'unittest.types', 'unittest.util', 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Using fontManager instance from /home/ben/.matplotlib/fontList.cache
backend Qt4Agg version 0.9.1
findfont: Matching :family=sans-serif:style=normal:variant=normal:weight=normal:stretch=normal:size=medium to Bitstream Vera Sans (/usr/lib/python2.7/site-packages/matplotlib/mpl-data/fonts/ttf/Vera.ttf) with score of 0.000000