I gave a colleague a matplotlib script that generated a .ps output with
savefig, and was surprised when it didn't work for him. I eventually
figured out that since he was a Windows user and didn't have DISPLAY set,
the import of the matplotlib libraries was failing with the error in this
message's subject. I eventually solved the problem by doing
"matplotlib.use('PS')" before the pylab import.
However, the script never tried to actually display anything, it only
created the plot and did a savefig at the end. So my question is: is
this "could not open display" behavior at import the way things are
supposed to work, or is this a bug? It seems like it would be better to
hold off on the "could not open display" error until someone actually
tried to display something, and if all they did was savefigs, everything
would work fine.
This is on matplotlib .80.