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The current example program for RNGs is trivial, and only shows how to set a seed. We need a more elaborate example that shows: how to initialize a new RNG how to use it to generate random numbers how to set it as the

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igraph has some examples in the documentation. We need more short educational example programs. Contributions of such examples are very welcome. If you would like to contribute, please post in this thread and ask for

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What is the feature or improvement you would like to see? We currently have the following lattice graph generators: igraphsquarelattice(), n-dimensional igraphtriangularlattice(), 2d in various shapes

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What is the feature or improvement you would like to see? igraphcontractvertices() requires a mapping as input. This is almost always inconvenient. There should be alternative interfaces to contraction that: Take groups

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What is the feature or improvement you would like to see? A concise but mathematically precise description of the requested feature. I would like the ability to suppresse all degree-2 nodes from a graph in the following

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What is the feature or improvement you would like to see? Implement LinkRank, which is the equivalent of PageRank: what fraction of its time does a random walker spend on each edge? This is already implemented in

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Create additional clique finder benchmarks, which exercise all clique finder and independent set functions. Make sure that all cases are covered, including sparse and dense graphs. Currently, at least the following have

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We need tests that double check cut results. In particular, tests should check (1) whether a cut is indeed an incorrect cut (i.e. after removing the proposed edges/vertices in the cut/separators, we should double check

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What is the feature or improvement you would like to see? This issue is to implement functionality for computing the rich-club coefficient / function of a network. The functionality should be sufficiently flexible to

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What is the feature or improvement you would like to see? We now have igraphbiadjacency() and igraphgetbiadjacency() for unweighted dense biadjacency matrices. This is a feature request to add support for weighted and

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What is the feature or improvement you would like to see? igraphcontractvertices() requires a mapping vector as input. This is inconvenient to construct in the typical situation of starting with a set of vertex groups

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What is the feature or improvement you would like to see? A function that returns the condensation of the directed graph. The condensation of a directed graph is obtained by contracting each strongly connected component

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The multiplicity argument to bipartiteprojection acts as a count of the number of nodes of the first mode that two nodes of the second mode are both connected to, and vice versa. It would be useful to allow functions to

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What is the feature or improvement you would like to see? The "DIMACS formats" are a family of easy-to-parse formats for input data to various combinatorial problems put forward in the DIMACS challenges. Several of

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Right now the examples/simple directory contains both tests and examples linked from the documentation. Many of these "examples" are not actually useful as sample code. These should be identified and moves to

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What is the feature or improvement you would like to see? The vertices of the Kneser graph K(n,k) are the k-element subsets of n elements. Two vertices are connected precisely when the subsets are disjoint. This task is

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The igraph tutorial (here online, source file here) should be reviewed: Is it up to date? Is it understandable by a newcomer? Are essential points unexplained or missing? Ideally, this should be done by someone who is

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What is the feature or improvement you would like to see? A function that computes the graph center, and the graph periphery. The graph center is the set of vertices that has minimal eccentricity. The periphery is the

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Currently spaces are used. It would be useful to be able to write a standard csv or tsv file, for

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