I've used both pygame and PIL for this in the past. (i'm plotting a non-standard 3d data format from a in-house app) Pygame was nice because I put a key handler in to reload the file and do a little zooming/panning and when I wanted to save a particular plot I would just use a screen capture program. Then I upgraded my harddrive and didn't re-install PyGame. The next time I had to plot some data, I tweaked my script to use PIL. I ended up liking this solution better. I could easily create large images (bigger than physical screen which was a limiting factor in PyGame) and used a regular image viewer to pan and shrink/zoom. I had the drawing portions of my script well separated from the data parsing and manipulation so tweaking the script was simple.
YMMV, but PIL was the best way for me. ... jay graves -- http://mail.python.org/mailman/listinfo/python-list
