obspy/obspy — pull request #813 by bmorg (2014-06-02 14:49:35+00:00)
Title: Use pcolormesh for plotting PPSD

In 51e593d `pcolor` is replaced by `pcolormesh`, which results in the exact same plot, but has a huge performance benefit (almost factor 10 for plotting a single day on my machine).

See also [matplotlib documentation](http://matplotlib.org/1.3.1/api/pyplot_api.html#matplotlib.pyplot.pcolormesh).