# Latest **URL:** https://igraph.discourse.group/latest.md [Latest](https://igraph.discourse.group/latest.md) · [Categories](https://igraph.discourse.group/categories.md) · [Tags](https://igraph.discourse.group/tags.md) --- ## [How to contribute?](https://igraph.discourse.group/t/how-to-contribute/1350)
**Author:** [@szhorvat](https://igraph.discourse.group/u/szhorvat)\ **Replies:** 0\ **Last updated:** [6 September 2022 09:59 UTC](https://igraph.discourse.group/t/how-to-contribute/1350 "2022-09-06T09:59:01Z")
igraph, as an open-source project, thrives on the contributions of volunteers like you. We can always use more help, and you can get involved in many different ways: Use igraph, give feedback, report any problems you f… --- ## [How to use this forum?](https://igraph.discourse.group/t/how-to-use-this-forum/35)
**Author:** [@szhorvat](https://igraph.discourse.group/u/szhorvat)\ **Replies:** 0\ **Last updated:** [28 January 2020 22:25 UTC](https://igraph.discourse.group/t/how-to-use-this-forum/35 "2020-01-28T22:25:49Z")
If you are new to the Discourse platform, which we are using for this forum, the Discourse New User Guide will show you the basics. In short, text is formatted using Markdown (recommended), BBCode or HTML. The examples… --- ## [Welcome to the igraph discussion forum!](https://igraph.discourse.group/t/welcome-to-the-igraph-discussion-forum/7)
**Author:** [@system](https://igraph.discourse.group/u/system)\ **Replies:** 0\ **Last updated:** [4 September 2019 07:13 UTC](https://igraph.discourse.group/t/welcome-to-the-igraph-discussion-forum/7 "2019-09-04T07:13:22Z")
Welcome to the igraph discussion forum! Please see https://igraph.discourse.group/t/how-to-use-this-forum/35/2 for help on how to post. This forum is a place to discuss network analysis and graph theory calculations wit… --- ## [Permission/license for using the igraph logo in a journal figure](https://igraph.discourse.group/t/permission-license-for-using-the-igraph-logo-in-a-journal-figure/2257)
**Author:** [@carissableker](https://igraph.discourse.group/u/carissableker)\ **Replies:** 1\ **Last updated:** [25 August 2026 11:49 UTC](https://igraph.discourse.group/t/permission-license-for-using-the-igraph-logo-in-a-journal-figure/2257 "2026-08-25T11:49:58Z")
We’re preparing a paper for a Python package that supports igraph interoperability, and we’d like to include the igraph logo in a figure. Similar to Fig 3 of the recent igraph paper (Antonov et al., 2026, PLoS One, igra… --- ## [Rust igraph bindings](https://igraph.discourse.group/t/rust-igraph-bindings/1828)
**Author:** [@theCapypara](https://igraph.discourse.group/u/theCapypara)\ **Replies:** 6\ **Last updated:** [5 August 2026 10:31 UTC](https://igraph.discourse.group/t/rust-igraph-bindings/1828 "2026-08-05T10:31:59Z")
Hello! I am soon migrating a project of mine written in Python to Rust and since I am using igraph, would like to port bindings for that as well :slight\_smile: I see that a previous attempt at Rust bindings for igraph … --- ## [python-igraph C Extension Analysis Report](https://igraph.discourse.group/t/python-igraph-c-extension-analysis-report/2233)
**Author:** [@devdanzin](https://igraph.discourse.group/u/devdanzin)\ **Replies:** 10\ **Last updated:** [27 July 2026 14:53 UTC](https://igraph.discourse.group/t/python-igraph-c-extension-analysis-report/2233 "2026-07-27T14:53:09Z")
Hello, I ran a code review tool I develop on igraph and got interesting results from it. Below’s an overview, and the full report is available at python-igraph C Extension Analysis Report · GitHub. I hope it helps. Ple… --- ## [Get parts of the transitivity ratio](https://igraph.discourse.group/t/get-parts-of-the-transitivity-ratio/2243)
**Author:** [@Zilch](https://igraph.discourse.group/u/Zilch)\ **Replies:** 2\ **Last updated:** [2 June 2026 16:38 UTC](https://igraph.discourse.group/t/get-parts-of-the-transitivity-ratio/2243 "2026-06-02T16:38:19Z")
Hi there. I’m trying to get both parts of the transitivity ratio, i.e. number:number, instead the 0-1 value. I tried using the triangles and graph.motifs.no function for motifs of triads but the code under provides resul… --- ## [Issue verifying betweenness centrality for a directed graph in R](https://igraph.discourse.group/t/issue-verifying-betweenness-centrality-for-a-directed-graph-in-r/2242)
**Author:** [@Dr-Eti](https://igraph.discourse.group/u/Dr-Eti)\ **Replies:** 4\ **Last updated:** [30 April 2026 14:58 UTC](https://igraph.discourse.group/t/issue-verifying-betweenness-centrality-for-a-directed-graph-in-r/2242 "2026-04-30T14:58:35Z")
Consider a simple R object containing the following edge list for a directed graph: myArcs\_igraph source\_node\_ISO target\_node\_ISO 1 FR BE 2 NL BE 3 … --- ## [\[GSoC 2026\] Interested in Community Detection Guide: introduction](https://igraph.discourse.group/t/gsoc-2026-interested-in-community-detection-guide-introduction/2232)
**Author:** [@Jacopo888](https://igraph.discourse.group/u/Jacopo888)\ **Replies:** 1\ **Last updated:** [23 March 2026 06:37 UTC](https://igraph.discourse.group/t/gsoc-2026-interested-in-community-detection-guide-introduction/2232 "2026-03-23T06:37:05Z")
Hi everyone, I’m Jacopo, a third-year Mathematical Engineering student at Politecnico di Milano, with a focus on algorithms, graph theory, and probabilistic methods. I’m interested in the Community Detection Guide ment… --- ## [mst() for directed graphs?](https://igraph.discourse.group/t/mst-for-directed-graphs/2226)
**Author:** [@DOSull](https://igraph.discourse.group/u/DOSull)\ **Replies:** 4\ **Last updated:** [28 January 2026 10:21 UTC](https://igraph.discourse.group/t/mst-for-directed-graphs/2226 "2026-01-28T10:21:57Z")
Hi, I am in a situation where I’m using mst() (in igraph R) but on directed graphs. I know that this is not formally correct, and that e.g., networkx can find arborescences which might be more ‘correct’. However the min… --- ## [edge\_betweenness output vector coerced to dist matrix?](https://igraph.discourse.group/t/edge-betweenness-output-vector-coerced-to-dist-matrix/2220)
**Author:** [@drakej](https://igraph.discourse.group/u/drakej)\ **Replies:** 0\ **Last updated:** [23 January 2026 21:58 UTC](https://igraph.discourse.group/t/edge-betweenness-output-vector-coerced-to-dist-matrix/2220 "2026-01-23T21:58:56Z")
I am trying to conduct a correlative analysis where in I am trying to relate the pairwise edge betweenness values to a pairwise genetic value. I have been unable to determine how to coerce the vector that edge\_betweenne… --- ## [How to calculate assortativity for weighted directed graphs?](https://igraph.discourse.group/t/how-to-calculate-assortativity-for-weighted-directed-graphs/2211)
**Author:** [@rosario](https://igraph.discourse.group/u/rosario)\ **Replies:** 1\ **Last updated:** [26 December 2025 19:08 UTC](https://igraph.discourse.group/t/how-to-calculate-assortativity-for-weighted-directed-graphs/2211 "2025-12-26T19:08:51Z")
I want to define the methodology for my thesis, but RStudio obtains a different value from mine for assortativity. My graph is directed, a multigraph, and has weighted degrees. The equation that I think igraph uses (and … --- ## [C/igraph 1.0.1](https://igraph.discourse.group/t/c-igraph-1-0-1/2212)
**Author:** [@system](https://igraph.discourse.group/u/system)\ **Replies:** 0\ **Last updated:** [26 December 2025 12:19 UTC](https://igraph.discourse.group/t/c-igraph-1-0-1/2212 "2025-12-26T12:19:44Z")
C/igraph 1.0.1, the first bugfix release of the 1.0 series, has arrived, with bug fixes and documentation improvements. This is a companion discussion topic for the original entry at https://igraph.org/2025/12/26/igrap… --- ## [Steering committee - new chair](https://igraph.discourse.group/t/steering-committee-new-chair/2209)
**Author:** [@vtraag](https://igraph.discourse.group/u/vtraag)\ **Replies:** 0\ **Last updated:** [15 December 2025 15:05 UTC](https://igraph.discourse.group/t/steering-committee-new-chair/2209 "2025-12-15T15:05:27Z")
Last year, we setup a more detailed governance structure for igraph, with Fabio Zanini, Szabolcs Horvát and me forming the inaugural steering committee. We also appointed coordinators for the various interfaces: C core… --- ## [R package igraph 2.2.1 failed installation, undefined symbol: glp\_at\_error](https://igraph.discourse.group/t/r-package-igraph-2-2-1-failed-installation-undefined-symbol-glp-at-error/2208)
**Author:** [@RAYMOND\_BENITEZ](https://igraph.discourse.group/u/RAYMOND_BENITEZ)\ **Replies:** 3\ **Last updated:** [1 December 2025 21:07 UTC](https://igraph.discourse.group/t/r-package-igraph-2-2-1-failed-installation-undefined-symbol-glp-at-error/2208 "2025-12-01T21:07:08Z")
When I try to install igraph 2.2.1 in R on a cluster (CentOS Linux), I receive the following error. Error: package or namespace load failed for ‘igraph’ in dyn.load(file, DLLpath = DLLpath, …): unable to load shared obj… --- ## [IGraphs.jl the julia wrapper for igraph now supports igraph 1.0.0](https://igraph.discourse.group/t/igraphs-jl-the-julia-wrapper-for-igraph-now-supports-igraph-1-0-0/2207)
**Author:** [@Krastanov](https://igraph.discourse.group/u/Krastanov)\ **Replies:** 0\ **Last updated:** [25 September 2025 15:50 UTC](https://igraph.discourse.group/t/igraphs-jl-the-julia-wrapper-for-igraph-now-supports-igraph-1-0-0/2207 "2025-09-25T15:50:30Z")
IGraphs.jl is a low-level wrapper for igraph in Julia. It provides access to igraph on arm/amd64 windows/mac/linux. It now wraps igraph 1.0.0 Here is a quick example of IGraphs.jl used together with the julia Graphs.j… --- ## [Clarification on subgraph function and sample-specific information](https://igraph.discourse.group/t/clarification-on-subgraph-function-and-sample-specific-information/2206)
**Author:** [@H\_Charlie](https://igraph.discourse.group/u/H_Charlie)\ **Replies:** 3\ **Last updated:** [25 September 2025 06:17 UTC](https://igraph.discourse.group/t/clarification-on-subgraph-function-and-sample-specific-information/2206 "2025-09-25T06:17:29Z")
Hello, thank you for the great tool! I have a question regarding the use of the subgraph function in building single-sample subnetworks. From what I understand, the current implementation takes the global network and th… --- ## [C/igraph 1.0.0](https://igraph.discourse.group/t/c-igraph-1-0-0/2203)
**Author:** [@system](https://igraph.discourse.group/u/system)\ **Replies:** 0\ **Last updated:** [19 September 2025 22:04 UTC](https://igraph.discourse.group/t/c-igraph-1-0-0/2203 "2025-09-19T22:04:09Z")
Nearly twenty years after the first igraph release, igraph 1.0 has finally arrived. This release focuses on providing a stable and more consistent interface that users and downstream maintainers can rely on with confiden… --- ## [C/igraph 0.10.17](https://igraph.discourse.group/t/c-igraph-0-10-17/2202)
**Author:** [@system](https://igraph.discourse.group/u/system)\ **Replies:** 0\ **Last updated:** [19 September 2025 12:20 UTC](https://igraph.discourse.group/t/c-igraph-0-10-17/2202 "2025-09-19T12:20:01Z")
C/igraph 0.10.17, the (hopefully) last bugfix release of the 0.10 series, has arrived, with several new additions, bug fixes and performance improvements. As usual, the source can be obtained from the GitHub releases pag… --- ## [How to correctly calculate betweenness, closeness, and modularity in a weighted, undirected graph with negative weights？](https://igraph.discourse.group/t/how-to-correctly-calculate-betweenness-closeness-and-modularity-in-a-weighted-undirected-graph-with-negative-weights/2200)
**Author:** [@H\_Charlie](https://igraph.discourse.group/u/H_Charlie)\ **Replies:** 3\ **Last updated:** [17 September 2025 12:28 UTC](https://igraph.discourse.group/t/how-to-correctly-calculate-betweenness-closeness-and-modularity-in-a-weighted-undirected-graph-with-negative-weights/2200 "2025-09-17T12:28:09Z")
I have a question regarding the best practices for calculating centrality metrics and community structure in weighted, undirected networks that contain both positive and negative edge weights (representing correlations). … --- ## [all relation ship between two vertices in a DAG](https://igraph.discourse.group/t/all-relation-ship-between-two-vertices-in-a-dag/2196)
**Author:** [@grocanar](https://igraph.discourse.group/u/grocanar)\ **Replies:** 4\ **Last updated:** [24 August 2025 21:12 UTC](https://igraph.discourse.group/t/all-relation-ship-between-two-vertices-in-a-dag/2196 "2025-08-24T21:12:40Z")
Hi I am an old user of GRAMPS software to make my genealogy. Amd i m wondering if python-igrah can overcome some low speed troutine in GRAMPS. Especially for instance to find all relatinship path between two person. T… --- ## [Creating Preferential Attachment (PA) Complex Networks with Self Loops](https://igraph.discourse.group/t/creating-preferential-attachment-pa-complex-networks-with-self-loops/2191)
**Author:** [@benyamindsmith](https://igraph.discourse.group/u/benyamindsmith)\ **Replies:** 7\ **Last updated:** [12 August 2025 20:23 UTC](https://igraph.discourse.group/t/creating-preferential-attachment-pa-complex-networks-with-self-loops/2191 "2025-08-12T20:23:07Z")
I am trying to create a directed simulated preferential attachment complex network with self loops, similar to something like this: (This is the oncology\_network dataset available in the ig.degree.betweenness package.… --- ## [set up seed for community\_leiden](https://igraph.discourse.group/t/set-up-seed-for-community-leiden/2193)
**Author:** [@JellyZhangxc](https://igraph.discourse.group/u/JellyZhangxc)\ **Replies:** 5\ **Last updated:** [11 August 2025 22:57 UTC](https://igraph.discourse.group/t/set-up-seed-for-community-leiden/2193 "2025-08-11T22:57:35Z")
Hi, there is there any way we could set up a seed for community\_leiden? thanks seems kwds does not support any other argument except resolution\_parameter --- ## [Announce: passagemath-graphs 10.6.1, now with support for Windows](https://igraph.discourse.group/t/announce-passagemath-graphs-10-6-1-now-with-support-for-windows/2190)
**Author:** [@mkoeppe](https://igraph.discourse.group/u/mkoeppe)\ **Replies:** 0\ **Last updated:** [3 August 2025 04:17 UTC](https://igraph.discourse.group/t/announce-passagemath-graphs-10-6-1-now-with-support-for-windows/2190 "2025-08-03T04:17:23Z")
passagemath-graphs (passagemath-graphs · PyPI) is one of the pip-installable components of the modularized SageMath library, developed by the passagemath project. It supports CPython 3.10-3.13. passagemath-graphs consis… --- ## [Find minimum number of individuals](https://igraph.discourse.group/t/find-minimum-number-of-individuals/2188)
**Author:** [@Ross\_Ahmed](https://igraph.discourse.group/u/Ross_Ahmed)\ **Replies:** 0\ **Last updated:** [27 July 2025 11:30 UTC](https://igraph.discourse.group/t/find-minimum-number-of-individuals/2188 "2025-07-27T11:30:02Z")
I have a tibble with two columns and 312 rows: individual and different. The column individual is an integer vector with numbers 1 to 312. The column different is a character vector with each row listing individuals that… --- ## [graph\_from\_adjacency\_matrix with NAs on diagonal returning error: feature or bug?](https://igraph.discourse.group/t/graph-from-adjacency-matrix-with-nas-on-diagonal-returning-error-feature-or-bug/2172)
**Author:** [@jmoody77](https://igraph.discourse.group/u/jmoody77)\ **Replies:** 6\ **Last updated:** [2 July 2025 18:30 UTC](https://igraph.discourse.group/t/graph-from-adjacency-matrix-with-nas-on-diagonal-returning-error-feature-or-bug/2172 "2025-07-02T18:30:25Z")
Hi - When running igraph 2.1.4.9055 I’m finding a new behavior where NAs on the diagonal of an adjacency matrix now return an error (never used to). Is this known/deliberate behavior? Thank you! --- ## [All topological sorting arrangements of a DAG](https://igraph.discourse.group/t/all-topological-sorting-arrangements-of-a-dag/1151)
**Author:** [@mb208](https://igraph.discourse.group/u/mb208)\ **Replies:** 3\ **Last updated:** [1 July 2025 23:47 UTC](https://igraph.discourse.group/t/all-topological-sorting-arrangements-of-a-dag/1151 "2025-07-01T23:47:20Z")
Hi all, I noticed that there is a topological sort method that gives a topological sorting of the vertices of a DAG, but this seems to only return 1 arrangement. I was wondering if there was a method that returns all po… --- ## [ig\_degree\_betweenness - The Python Implementation of "Smith-Pittman" Clustering](https://igraph.discourse.group/t/ig-degree-betweenness-the-python-implementation-of-smith-pittman-clustering/2168)
**Author:** [@benyamindsmith](https://igraph.discourse.group/u/benyamindsmith)\ **Replies:** 0\ **Last updated:** [22 June 2025 16:38 UTC](https://igraph.discourse.group/t/ig-degree-betweenness-the-python-implementation-of-smith-pittman-clustering/2168 "2025-06-22T16:38:42Z")
Happyt to share the Python implementation of ig.degree.betweenness. Leverage node degree and edge betweenness in community detection with this Girvan-Newman styled algorithm. Install with pip install ig-degree-betweenn… --- ## [Find cycles in graph](https://igraph.discourse.group/t/find-cycles-in-graph/2165)
**Author:** [@iFoxz](https://igraph.discourse.group/u/iFoxz)\ **Replies:** 1\ **Last updated:** [11 June 2025 09:29 UTC](https://igraph.discourse.group/t/find-cycles-in-graph/2165 "2025-06-11T09:29:33Z")
I have installed python-igraph with pip (version 0.11.8). I created a directed graph but I am not able to access the function simple\_cycles reported in the doc. I found in the C documentation that the related functions… --- ## [Callback in Python igraph Traversal Algorithms](https://igraph.discourse.group/t/callback-in-python-igraph-traversal-algorithms/1517)
**Author:** [@nparham](https://igraph.discourse.group/u/nparham)\ **Replies:** 2\ **Last updated:** [10 June 2025 13:51 UTC](https://igraph.discourse.group/t/callback-in-python-igraph-traversal-algorithms/1517 "2025-06-10T13:51:25Z")
Is it not possible to specify a callback for BFS/DFS in igraph via the Python API? If not, is this not a feature on purpose? I am wondering why R seems to have more functionality than Python with respect to igraph featur… [Next page](https://igraph.discourse.group/latest.md?page=1)