Octave Pythonic Package

Pythonic is a package that provides a Python native calling interface for GNU Octave.

Usage

Install this package in Octave using the pkg command

pkg install https://gitlab.com/mtmiller/octave-pythonic/-/archive/v0.0.1/octave-pythonic-v0.0.1.tar.gz

or download and install in the command shell

curl -O https://gitlab.com/mtmiller/octave-pythonic/-/archive/v0.0.1/octave-pythonic-v0.0.1.tar.gz
octave --eval "pkg install octave-pythonic-v0.0.1.tar.gz"

Load the package before using it

pkg load pythonic

Once the package is loaded, any available Python class or function can be invoked with the py package prefix. A few very basic examples to get started are listed here.

• Add a directory to the Python module search path

  py.sys.path.insert (int32 (0), "/path/to/module");
  

• Use a vectorized NumPy function

  x = py.numpy.sqrt (1:10);
  

• Call a function with keyword arguments

  a = py.int ("5ba0", pyargs ("base", int32 (16)));
  

• Read an entire text file into a string

  s = py.str ().join (py.open ("/etc/motd").readlines ());
  

Python Selection

The specific Python used by the package is selected when the package is installed. It is compiled in to the installed package and cannot currently be changed dynamically. To check which Python is used, use the pyversion command

>> pkg load pythonic
>> pyversion
       version: "3.7"
    executable: "/usr/bin/python3"
       library: "/usr/lib/x86_64-linux-gnu/libpython3.7m.so"
        prefix: "/usr"
        loaded: 1

The default is to use the python program found by a standard path search. Use the PYTHON or PYTHON_VERSION environment variables to override the default. For example

>> setenv PYTHON_VERSION 3
>> pkg install …

or

>> setenv PYTHON /home/user/anaconda3/bin/python
>> pkg install …

You may have to ensure that your system has Python installed properly. Some GNU/Linux distributions may require separate installation of the Python header files and development libraries (e.g. python-dev for Debian).

Goals

The goals of this package include

• call any loadable Python modules, classes, and functions
• hold reference to and operate on any Python data type as Octave variables
• translate certain Octave data types into Python arguments automatically
• translate certain Python data types into Octave return values automatically
• be as compatible as possible with Matlab's Python calling interface

Development

This package also supports building, using, and testing directly from the code repository.

git clone https://gitlab.com/mtmiller/octave-pythonic.git
cd octave-pythonic
make
make check
octave --path $PWD/inst --path $PWD/src

The build system can be configured to use a separate object directory, for example to build with two different versions of Python

mkdir py2 py3
make O=py2 PYTHON_VERSION=2
make O=py3 PYTHON_VERSION=3

Get Involved

This Octave package is maintained at mtmiller/octave-pythonic on GitLab.

If you want to contribute in any way and help make this package better, please read the contribution guidelines.

License

This package is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. See COPYING for the full license text.