igraph – The network analysis package

igraph is a collection of network analysis tools with the emphasis on efficiency, portability and ease of use. igraph is open source and free. igraph can be programmed in R, Python and C/C++.

igraph R package python-igraph igraph C library

January 16, 2015

A couple of days ago we changed how we use Github for igraph development. Our goal is to make igraph development more accessible, and our build process simpler. Instead of using a common repository for everything, we now use separate repos for the igraph C library, the R package and the Python extension. The igraph.org website was already in a separate repository, and we will also break up the R package, by putting loosely coupled parts in their own packages and repositories.

Main igraph repositories now:


April 21, 2014

Release Notes

Some bug fixes, to make sure that the code included in 'Statistical Analysis of Network Data with R' works. See https://github.com/kolaczyk/sand

Detailed changes:

  • Graph drawing: fix labels of curved edges, issue #181.
  • Graph drawing: allow fixing edge labels at given positions, issue #181.
  • Drop the 'type' vertex attribute after bipartite projection, the projections are not bipartite any more, issue #255.
  • Print logical attributes in header properly (i.e. encoded by l, not x, which is for complex attributes. Issue #578.
  • Add a constructor for communities objects, see create.communities(). Issue #547.
  • Better error handling in the GraphML parser.
  • GraphML reader is a bit more lenient now; makes it possible to read GraphML files saved from yWorks apps.
  • Fixed a bug in constaint(), issue #580.
  • Bipartite projection now detects invalid edges instead of giving a cryptic error, issue #543.
  • Fixed the simplify argument of graph.formula(), which was broken, issue #586.
  • The function crossing() adds better names to the result, fixes issue #587.
  • The sir() function gives an error if the input graph is not simple, fixes issue #582.
  • Calling igraph functions from igraph callbacks is not allowed now, fixes issue #571.

April 21, 2014

Release Notes

Some bug fixes, to make sure that the code included in 'Statistical Analysis of Network Data with R' works. See http://github.com/kolaczyk/sand

Detailed changes:

  • Better error handling in the GraphML parser.
  • GraphML reader is a bit more lenient now; makes it possible to read GraphML files saved from yWorks apps.
  • Fixed a bug in igraph_constaint(), issue #580.
  • Bipartite projection now detects invalid edges instead of giving a cryptic error, issue #543.
  • Bipartite projection now detects invalid edges instead of giving a cryptic error, issue #543.

February 4, 2014

Release Notes

There are a bunch of new features in the library itself, and other important changes in the life of the project. Thanks everyone for sending code and reporting bugs!

igraph @ github

igraph's development has moved from Launchpad to github. This has actually happened several month ago, but never announced officially. The place for reporting bugs is at https://github.com/igraph/igraph/issues.

New homepage

igraph's homepage is now hosted at http://igraph.org, and it is brand new. We wanted to make it easier to use and modern.

More →


February 4, 2014

Release Notes

There are a bunch of new features in the library itself, and other important changes in the life of the project. Thanks everyone for sending code and reporting bugs!

igraph @ github

igraph's development has moved from Launchpad to github. This has actually happened several month ago, but never announced officially. The place for reporting bugs is at https://github.com/igraph/igraph/issues.

New homepage

igraph's homepage is now hosted at http://igraph.org, and it is brand new. We wanted to make it easier to use and modern.

More →


February 4, 2014

Release Notes

There are a bunch of new features in the library itself, and other important changes in the life of the project. Thanks everyone for sending code and reporting bugs!

igraph @ github

igraph's development has moved from Launchpad to github. This has actually happened several month ago, but never announced officially. The place for reporting bugs is at https://github.com/igraph/igraph/issues.

New homepage

The igraph library's homepage is now hosted at http://igraph.org/c, and it is brand new. We wanted to make it easier to use and better to look at.

More →


February 24, 2013

The version number is not a mistake, we jump to 0.6.5 from 0.6, for technical reasons.

Release Notes

igraph 0.6.5 is a minor release that contains only few big changes, and fixes a number of very annoying bugs.

See at the end for the complete list of changes. First let's see the most important new features and changes.

More →


February 24, 2013

The version number is not a mistake, we jump to 0.6.5 from 0.6, for technical reasons.

Release Notes

igraph 0.6.5 is a minor release that contains only few big changes, and fixes a number of very annoying bugs.

See at the end for the complete list of changes. First let's see the most important new features and changes.

More →


February 24, 2013

The version number is not a mistake, we jump to 0.6.5 from 0.6, for technical reasons.

Release Notes

igraph 0.6.5 is a minor release that contains only few big changes, and fixes a number of very annoying bugs.

See at the end for the complete list of changes. First let's see the most important new features and changes.

More →


June 11, 2012

Release Notes

igraph 0.6 is a major new release of igraph. It contains many new features and major changes, a lot of bug fixes and improvements. As always, we are grateful to the people who sent comments, bug reports, questions, and specially to people who contributed code.

See below a list of major changes, with links to the relevant sections of the documentation. New features in R all listed here.

See at the end for a (more) complete list of changes.

More →


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