Use frombuffer and copy instead, since it's Python 3.x compatible.

Author: mdboom

examples/pylab_examples/agg_buffer_to_array.py

@@ -12,7 +12,9 @@
 # grab the pixel buffer and dump it into a numpy array
 buf = fig.canvas.buffer_rgba()
 l, b, w, h = fig.bbox.bounds
-X = np.fromstring(buf, np.uint8)
+# The array needs to be copied, because the underlying buffer
+# may be reallocated when the window is resized.
+X = np.frombuffer(buf, np.uint8).copy()
 X.shape = h,w,4
 
 # now display the array X as an Axes in a new figure