Jean-Michel> It seems that show() hangs if no figure has been
Jean-Michel> created before calling (under matplotlib 0.62.4). Am
Jean-Michel> I wrong or is it an unexpected use of show() ?
show should be the last line of your script. It is expected to hang.
It starts the GUI mainloop after which all processing is done in the
GUI event handling (unless you are using threading).
See http://matplotlib.sf.net/faq.html#SHOW
JDH