Problems "animated" plot

Hall?chen! John Hunter <jdhunter@...4...>

    > writes:

    >>>>>>> "Torsten" == Torsten Bronger
    >>>>>>> <bronger@...669...> writes:
    > 2. The above loop is the last part of my program. The
    > program terminates with
    > Fatal Python error: PyEval_RestoreThread: NULL tstate
    > Apparently, this is done by my improper handling of
    > matplotlib. What's going wrong?
    >> This is an annoyance we haven't been able to get rid of in all
    >> use cases. animation using pylab and tkagg is one of the
    >> places. I assume you are using the tkagg backend?

    > Yes.

    >> If you search the mailing list archives for
    >> PyEval_RestoreThread, you'll see this in many contexts. For
    >> any semi-serious animation work, I suggest you not use the
    >> matplotlib/interactive mode shown in but rather use
    >> your GUI's idle handling or timer mechanism as in
    >> examples/ or examples/

    > Thanks, I'll do.

    >> [...]
    > 3. How can I achieve that dynamic autoscaling of the
    > y-axis? As noted in the source, "gcf().autoscale_view"
    > has no effect.
    >> This is not legal matplotlib code -- I assume you mean
    >> gca().autoscale_view().

    > Yes, sorry.

    >> In the absence of more information it is hard top diagnose what
    >> the problem is.

    > Here is a complete example:

OK, that helps. The update of the data limits happens when you call
plot and friends (technically plot calls ax.add_line which calls
ax.update_datalim_numerix) . If you manually set the xdata or ydata
on the line object, you need to manually update the Axes datalim with

ax = gca()
for i in range(2*cycles):
    voltages = number_of_values * [i % 2 + 3]
    y_values[i * number_of_values : (i+1) * number_of_values] = \
    ax.update_datalim_numerix(x_values, y_values)