I am plotting three sets of roughly 20 time series. Each time series has 1.8 million points and I am plotting them separately. In order to reduce execution time (because I found out that the figure() function is quite time consuming), I open one figure only, plot and then clean it for the next time series. Something like:
import matplotlib.pyplot as plt
fig = plt.figure() # open a figure for plotting
for v in range(nfigs):
# here I build the x and y vectors from the raw data
# and also the figname string
plt.plot(x, y, linewidth=0.3)
plt.title('a title')
plt.xlabel('x-label')
plt.ylabel('y-label')
plt.grid()
plt.draw()
plt.savefig(figname)
plt.clf()
plt.close() # close the figure after the job is done
All the plots are saved ok except for one in particular in all the data sets which gives me the following error (edited the file paths for privacy):
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "~AppDataLocalContinuumAnacondalibsite-packagesspyderlibwidgetsexternalshellsitecustomize.py", line 540, in runfile
execfile(filename, namespace)
File "batch.py", line 142, in <module>
main(fn)
File "batch.py", line 94, in main
plt.savefig(figname+'_'+nn+'.png')
File "~AppDataLocalContinuumAnacondalibsite-packagesmatplotlibpyplot.py", line 561, in savefig
return fig.savefig(*args, **kwargs)
File "~AppDataLocalContinuumAnacondalibsite-packagesmatplotlibfigure.py", line 1421, in savefig
self.canvas.print_figure(*args, **kwargs)
File "~AppDataLocalContinuumAnacondalibsite-packagesmatplotlibackendsackend_qt4agg.py", line 167, in print_figure
FigureCanvasAgg.print_figure(self, *args, **kwargs)
File "~AppDataLocalContinuumAnacondalibsite-packagesmatplotlibackend_bases.py", line 2220, in print_figure
**kwargs)
File "~AppDataLocalContinuumAnacondalibsite-packagesmatplotlibackendsackend_agg.py", line 505, in print_png
FigureCanvasAgg.draw(self)
File "~AppDataLocalContinuumAnacondalibsite-packagesmatplotlibackendsackend_agg.py", line 451, in draw
self.figure.draw(self.renderer)
File "~AppDataLocalContinuumAnacondalibsite-packagesmatplotlibartist.py", line 55, in draw_wrapper
draw(artist, renderer, *args, **kwargs)
File "~AppDataLocalContinuumAnacondalibsite-packagesmatplotlibfigure.py", line 1034, in draw
func(*args)
File "~AppDataLocalContinuumAnacondalibsite-packagesmatplotlibartist.py", line 55, in draw_wrapper
draw(artist, renderer, *args, **kwargs)
File "~AppDataLocalContinuumAnacondalibsite-packagesmatplotlibaxes.py", line 2086, in draw
a.draw(renderer)
File "~AppDataLocalContinuumAnacondalibsite-packagesmatplotlibartist.py", line 55, in draw_wrapper
draw(artist, renderer, *args, **kwargs)
File "~AppDataLocalContinuumAnacondalibsite-packagesmatplotliblines.py", line 562, in draw
drawFunc(renderer, gc, tpath, affine.frozen())
File "~AppDataLocalContinuumAnacondalibsite-packagesmatplotliblines.py", line 938, in _draw_lines
self._lineFunc(renderer, gc, path, trans)
File "~AppDataLocalContinuumAnacondalibsite-packagesmatplotliblines.py", line 978, in _draw_solid
renderer.draw_path(gc, path, trans)
File "~AppDataLocalContinuumAnacondalibsite-packagesmatplotlibackendsackend_agg.py", line 145, in draw_path
self._renderer.draw_path(gc, path, transform, rgbFace)
OverflowError: Allocated too many blocks
The time series that triggers this error has absolutely nothing special about it, I have checked it with a simple show() instead of savefig(). It is neither the first one nor the last one (in roughly 60 time series) but it is enough to break my script. Help on this is much appreciated!
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