Hi, below is a simple script illustration what I wish to do:
> ==> use new symbols (here ellipses for example) and plot a
> number of points with 'scatter', allowing transparency
> (alpha=0.2) to see when two data points overlap. For some
> reason this works: 1/ on the figure 2/ when saving as .png
> but it does NOT work when saving as a Postscript file.
> Is there an easy solution for this? (I am using GTKAgg, mpl
> (doing a "convert" afterwards works but this is not very
> practical here)
Postscript does not support transparency -- this is a limitation of
postscript and not the matplotlib ps backend. If you want vector
graphics with transparency, you'll need SVG or PDF.