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

June 24, 2015

Release Notes

This is a new major release, with a lot of UI changes. We tried to make it easier to use, with short and easy to remember, consistent function names. Unfortunately this also means that many functions have new names now, but don't worry, all the old names still work.

Apart from the new names, the biggest change in this release is that most functions that used to return numeric vertex or edge ids, return vertex/edge sequences now. This requires some time to get used to and if you want the numeric ids instead, just use the as.vector() function on the vertex/edge sequences.

We will update the documentation on this site, once the package is on CRAN and available for all architectures.

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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 →


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