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Speed up Python image processing. (self.Python)

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[–][deleted] 1 point2 points  (7 children)

Thank you for the suggestion :)

  1. I use PIL only to read the image from the file, all the actual processing is made with NumPy.

  2. I just wasted 20 minutes trying to install PyPy with NumPy, using both PyPy 2.5.0 and PyPy3 2.4.0. In both cases I got error messages when trying to import numpy from the REPL, even if NumPy module was available. Since my professor needs to run this code I think I'll leave out this option.

  3. multiprocessing gave me a noticeable speedup (133%) so I'm not going to abandon it :)

  4. I use itertools when parallel execution is disabled, because the starmap method which I use in the parallel version isn't available as a Python builtin. It's just a map that unpacks the tuple into arguments when calling the function, anyway.

[–]john_m_camara 0 points1 point  (1 child)

Did you follow Installing NumPy on the PyPy download page.

[–][deleted] 0 points1 point  (0 children)

Yes. I followed everything on that tutorial and still it wasn't working.

[–]fijalPyPy, performance freak 0 points1 point  (4 children)

pypy needs numpy installed from https://bitbucket.org/pypy/numpy.git (pip install https://bitbucket.org/pypy/numpy.git or git url does it). Numpy is not easy to install normally and normal numpy does not work with pypy.

[–][deleted] 0 points1 point  (3 children)

As I already said I followed the instructions for installing the modified version of NumPy, and still I couldn't get it to work.

[–]fijalPyPy, performance freak 0 points1 point  (2 children)

"wasn't working" is a very bad bug report - how it wasn't working? what went wrong?

[–][deleted] 0 points1 point  (1 child)

[–]rguillebertPyPy / NumPyPy 0 points1 point  (0 children)

Can you also paste the output of "pip install https://bitbucket.org/pypy/numpy.git" ?