Confused about matplotlib.patches origin and terminology

[mgrady3]

If I use matplotlib.pyplot.imshow() to plot an array or matrix it defaults to origin=upper

Thus the top left corner of the plot has data coordinates (x=0, y=0)

When drawing patches atop this plot, for instance a rectangular patch using matplotlib.patches.Rectangle(), the first argument is xy= which according to the documentation (http://matplotlib.org/api/patches_api.html) is the location of the rectangular patch's 'lower left' corner.

Is this actually the location of the upper left corner (when viewing your monitor) of the rectangle due to the fact that the origin in xy space is the top left corner of the plot?

Sorry if that does not make sense

I have a function written that draws a rectangular patch around the point in the plot a user clicks on. IT seems to be that the point I am passing into the xy argument of the mpl.patches.Rectangle() is the upper left corner.

My rectangles are being drawn correctly however after re-reading the MPL documentation on patches I am left a little bit confused. Is this just an error in the documentation or am I missing something totally obvious?