Python interface for igraph
Python C Other
Latest commit 2917c0b Jan 23, 2017 @ntamas ntamas temporarily ignoring Nexus-related doctests until we decide what will…
… happen to

Python interface for the igraph library

igraph is a library for creating and manipulating graphs. It is intended to be as powerful (ie. fast) as possible to enable the analysis of large graphs.

This repository contains the source code to the Python interface of igraph.

You can learn more about python-igraph on our website.


$ sudo python install

See details in Installing Python Modules.

Compiling the development version

If you have downloaded the source code from Github and not PyPI, chances are that you have the latest development version, which might not be compatible with the latest release of the C core of igraph. Therefore, to install the bleeding edge version, you need to instruct the setup script to download the latest development version of the C core as well:

$ sudo python develop --c-core-url


This version of python-igraph is compatible with PyPy and is regularly tested on PyPy with tox. However, the PyPy version falls behind the CPython version in terms of performance; for instance, running all the tests takes ~5 seconds on my machine with CPython and ~15 seconds with PyPy. This can probably be attributed to the need for emulating CPython reference counting, and does not seem to be alleviated by the JIT.

There are also some subtle differences between the CPython and PyPy versions:

  • Docstrings defined in the C source code are not visible from PyPy.

  • GraphBase is hashable and iterable in PyPy but not in CPython. Since GraphBase is internal anyway, this is likely to stay this way.