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Odd aliasing issue with matplotlib

I was plotting some data collected from an ADC and noticed an odd aliasing issue. The images below are screen caps of the same plot simply with resizing of the window. The correct plot is the middle one that shows symmetric biphasic pulses.






I wonder if there is any way to avoid this kind of aliasing. I vaguely remember MATLAB handled this gracefully. I have found matplotlib's plotting to be superior to MATLAB's in every way (except for 3D) and it would be nice if aliasing could be handled gracefully.
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  1. AnonymousMarch 26, 2010 at 5:11 PM

    matplotlib does polyline simplification, which improves speed on highly oversampled data. The side-effect of this is the aliasing you've observed. I'm not sure how to turn polyline-simplification off.

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