markerfacecolor, imshow

On a different topic, imshow() only seems to display a single

    > image at a time. e.g. in the following example, when image2
    > is drawn image1 is deleted.
    > #------------------------------------------------- import
    > matplotlib.matlab as mat myImage = mat.imread('image1.png')
    > myImage2 = mat.imread('image2.png') mat.imshow(myImage,
    > extent=[0,1,0,1]) mat.imshow(myImage2, extent=[1,2,1,2])
    > mat.axis([0, 2, 0, 2]) mat.show()
    > #------------------------------------------------- Is that a
    > known issue? Is there a workaround?

    > all the best, Jon

Ahh, interesting case. I put the following line in the Axes.imshow
code to protect users from senselessly piling up lots of images

        if alpha==1: self._images = []

That is, I cleared the image stack if alpha was 1, reasoning you can't
see behind a fully opaque image; I was afraid someone might plot lots
of images to the same axes with alpha=1 , and never know they were
piling up images and hurting performance. I had neglected to consider
that you might be using multiple images with different extents.

If you comment out that line in matplotlib/axes.py, your example will
work.

Note that I find it a bit more natural to define separate axes to hold
the separate images. Of course, my approach won't work if you want to
plot other data, eg lines, that cover multiple images on the same
axes, but for simple montages, I think it's cleaner.

    import matplotlib.matlab as mat
    myImage = mat.imread('test1.png')
    myImage2 = mat.imread('test2.png')
    ax1 = mat.axes([0.5, 0.5, 0.5, 0.5])
    ax1.imshow(myImage)
    mat.axis('off')
    ax2 = mat.axes([0, 0.0, 0.5, 0.5])
    ax2.imshow(myImage2)
    mat.axis('off')
    mat.show()

JDH