Is there any way to encode 2 variables in a matplotlib colormap?  The idea is to replicate this dataspora R scatterplot in matplotlib:

http://www.dataspora.com/gameday/pitcher/daisuke-matsuzaka/493137

"The bottom strip of charts encode two dimensions with color -- blue or red hue indicates pitch velocity -- while the lightness or darkness of the hue indicates how many pitches were thrown in a given region. "


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Peter N. Skomoroch
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