I have been working on some offline processing of data and creating graphs on the fly which automatically get updated on a website. What has been problematic is to do this without a display (for example run from a cron job). I found a solution which seems to work with the EPD package I am using on a linux box.

[cc lang="python"]
from matplotlib.figure import Figure
from matplotlib.backends.backend_agg import FigureCanvasAgg

fig = Figure(figsize=(4,4))
fig.gca().plot(range(1,10))
canvas=FigureCanvasAgg(fig)
canvas.print_figure(‘bob.png’, dpi=150)
[/cc]

There are likely some other ways to do it, but this works for me.