Pythran

https://pythran.readthedocs.io

What is it?

Pythran is an ahead of time compiler for a subset of the Python language, with a focus on scientific computing. It takes a Python module annotated with a few interface descriptions and turns it into a native Python module with the same interface, but (hopefully) faster.

It is meant to efficiently compile scientific programs, and takes advantage of multi-cores and SIMD instruction units.

Until 0.9.5 (included), Pythran was supporting Python 3 and Python 2.7. It now only supports Python 3.

Installation

Pythran sources are hosted on https://github.com/serge-sans-paille/pythran.

Pythran releases are hosted on https://pypi.python.org/pypi/pythran.

Pythran is available on conda-forge on https://anaconda.org/conda-forge/pythran.

Debian/Ubuntu

Using pip

1. Gather dependencies:

   Pythran depends on a few Python modules and several C++ libraries. On a debian-like platform, run:

   $> sudo apt-get install libatlas-base-dev
   $> sudo apt-get install python-dev python-ply python-numpy
   

2. Install with pip:

   $> pip install pythran
   

Using mamba or conda

1. Using mamba (https://github.com/conda-forge/miniforge) or conda (https://github.com/conda-forge/miniforge)

2. Run:

   $> mamba install -c conda-forge pythran
   

   or:

   $> conda install -c conda-forge pythran
   

Mac OSX

Using brew (https://brew.sh/):

$> pip install pythran
$> brew install openblas
$> printf '[compiler]\nblas=openblas\ninclude_dirs=/usr/local/opt/openblas/include\nlibrary_dirs=/usr/local/opt/openblas/lib' > ~/.pythranrc

Depending on your setup, you may need to add the following to your ~/.pythranrc file:

[compiler]
CXX=g++-4.9
CC=gcc-4.9

ArchLinux

Using pacman:

$> pacman -S python-pythran

Fedora

Using dnf:

$> dnf install pythran

Windows

Windows support is on going and only targets Python 3.5+ with either Visual Studio 2017 or, better, clang-cl:

$> pip install pythran

Note that using clang-cl.exe is the default setting. It can be changed through the CXX and CC environment variables.

Other Platform

See MANUAL file.

Basic Usage

A simple pythran input could be dprod.py

"""
Naive dotproduct! Pythran supports numpy.dot
"""
#pythran export dprod(int list, int list)
def dprod(l0,l1):
    """WoW, generator expression, zip and sum."""
    return sum(x * y for x, y in zip(l0, l1))

To turn it into a native module, run:

$> pythran dprod.py

That will generate a native dprod.so that can be imported just like the former module:

$> python -c 'import dprod' # this imports the native module instead

Documentation

The user documentation is available in the MANUAL file from the doc directory.

The developer documentation is available in the DEVGUIDE file from the doc directory. There is also a TUTORIAL file for those who don't like reading documentation.

The CLI documentation is available from the pythran help command:

$> pythran --help

Some extra developer documentation is also available using pydoc. Beware, this is the computer science incarnation for the famous Where's Waldo? game:

$> pydoc pythran
$> pydoc pythran.typing
$> pydoc -b  # in the browser

Examples

See the pythran/tests/cases/ directory from the sources.

Contact

Praise, flame and cookies:

• pythran@freelists.org -- register at https://www.freelists.org/list/pythran first!
• #pythran on OFTC, https://oftc.net
• serge.guelton@telecom-bretagne.eu

The mailing list archive is available at https://www.freelists.org/archive/pythran/.

Citing

If you need to cite a Pythran paper, feel free to use

@article{guelton2015pythran,
  title={Pythran: Enabling static optimization of scientific python programs},
  author={Guelton, Serge and Brunet, Pierrick and Amini, Mehdi and Merlini,
                  Adrien and Corbillon, Xavier and Raynaud, Alan},
  journal={Computational Science \& Discovery},
  volume={8},
  number={1},
  pages={014001},
  year={2015},
  publisher={IOP Publishing}
}

Authors

See AUTHORS file.

License

See LICENSE file.