OpenMP Support

The setup.py script tests to see of OpenMP is available during installation. Unit tests executed by continuous integration currently do not test OpenMP.

Three methods are manually tested before releases:

  • Arch Linux: System python with extra/openmp installed (GCC 8.2).
  • macOS 10.14: Homebrew python3 with libomp installed from Homebrew (Apple LLVM version 10.0.0).
  • macOS 10.14: Anaconda python3 and python2 distributions with libomp installed from Homebrew (you probably need to remove the extra libiomp5.dylib from the Anaconda environment lib folder or conda install nomkl, see here).

To check if OpenMP was detected and used, try the following:

>>> import pygram11
>>> pygram11.OPENMP
True

Needless to say, if you see False OpenMP acceleration isn’t available.

The histogramming functions use a named argument for requesting OpenMP usage. If pygram11.OPENMP is False then the argument is ignored by the C++ code.