# \#C **URL:** https://igraph.discourse.group/tag/c/1.md [Latest](https://igraph.discourse.group/latest.md) · [Categories](https://igraph.discourse.group/categories.md) · [Tags](https://igraph.discourse.group/tags.md) --- ## [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 … --- ## [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… --- ## [Interested in GSoC Project: Spatial network analysis capabilities for igraph](https://igraph.discourse.group/t/interested-in-gsoc-project-spatial-network-analysis-capabilities-for-igraph/1957)
**Author:** [@Gulshan\_Kumar](https://igraph.discourse.group/u/Gulshan_Kumar)\ **Replies:** 6\ **Last updated:** [7 April 2025 14:06 UTC](https://igraph.discourse.group/t/interested-in-gsoc-project-spatial-network-analysis-capabilities-for-igraph/1957 "2025-04-07T14:06:10Z")
Hello everyone, My name is Gulshan Kumar, and I am a Computer Science & Engineering undergraduate at IIT Bombay. I am excited to contribute to igraph in GSoC 2025!. I have a strong background in C/C++ programming and c… --- ## [Interested in GSoC project named Degree-constrained null models and graph construction](https://igraph.discourse.group/t/interested-in-gsoc-project-named-degree-constrained-null-models-and-graph-construction/1943)
**Author:** [@Abhishek](https://igraph.discourse.group/u/Abhishek)\ **Replies:** 3\ **Last updated:** [21 March 2025 11:30 UTC](https://igraph.discourse.group/t/interested-in-gsoc-project-named-degree-constrained-null-models-and-graph-construction/1943 "2025-03-21T11:30:53Z")
Hii @szhorvat i am interested in this project. I have build and test the files. Can you please tell me how to use these files / igraph ? I am facing problem in this doc igraph Reference Manual --- ## [Weighted Perfect Matching (e.g. Blossom algorithm)](https://igraph.discourse.group/t/weighted-perfect-matching-e-g-blossom-algorithm/1934)
**Author:** [@Krastanov](https://igraph.discourse.group/u/Krastanov)\ **Replies:** 1\ **Last updated:** [6 March 2025 20:18 UTC](https://igraph.discourse.group/t/weighted-perfect-matching-e-g-blossom-algorithm/1934 "2025-03-06T20:18:25Z")
Is there a standard way to get maximum (or minimum) weight perfect matching in igraph? I think the standard approach for that is the Blossom algorithm. I do not think I see it listed in the documentation, but wanted to d… --- ## [C/igraph 0.10.15](https://igraph.discourse.group/t/c-igraph-0-10-15/1888)
**Author:** [@szhorvat](https://igraph.discourse.group/u/szhorvat)\ **Replies:** 0\ **Last updated:** [6 November 2024 22:38 UTC](https://igraph.discourse.group/t/c-igraph-0-10-15/1888 "2024-11-06T22:38:00Z")
C/igraph 0.10.15 is released now, with several new additions, bug fixes and performance improvements. Several functions were deprecated in preparation for the igraph 1.0 release. Notable improvements are a much faster ex… --- ## [C/igraph 0.10.11](https://igraph.discourse.group/t/c-igraph-0-10-11/1798)
**Author:** [@szhorvat](https://igraph.discourse.group/u/szhorvat)\ **Replies:** 8\ **Last updated:** [26 August 2024 12:31 UTC](https://igraph.discourse.group/t/c-igraph-0-10-11/1798 "2024-08-26T12:31:00Z")
C/igraph 0.10.11 is now released. As usual, the source can be obtained from the GitHub releases page. This release brings a large number of quality enhancements, including many bug fixes and performance improvements. Upg… --- ## [C/igraph 0.10.13](https://igraph.discourse.group/t/c-igraph-0-10-13/1824)
**Author:** [@szhorvat](https://igraph.discourse.group/u/szhorvat)\ **Replies:** 0\ **Last updated:** [28 June 2024 08:19 UTC](https://igraph.discourse.group/t/c-igraph-0-10-13/1824 "2024-06-28T08:19:40Z")
C/igraph 0.10.13 is released now, with several new additions, bug fixes and performance improvements. As usual, the source can be obtained from the GitHub releases page. A summary of changes is below. Added igraph\_bi… --- ## [Create a Graph in C-API, export for use in Python](https://igraph.discourse.group/t/create-a-graph-in-c-api-export-for-use-in-python/1376)
**Author:** [@Aaron\_Nowack](https://igraph.discourse.group/u/Aaron_Nowack)\ **Replies:** 10\ **Last updated:** [5 April 2024 19:55 UTC](https://igraph.discourse.group/t/create-a-graph-in-c-api-export-for-use-in-python/1376 "2024-04-05T19:55:48Z")
Hello igraph users, I’ve been using igraph effectively for visualizing neutrons in a fission chain (see this tweet of mine https://twitter.com/abnowack/status/1574508829647118337) I would like to speed this process up… --- ## [Is make\_line\_graph() in rigraph the same as in Mathematica, or as defined in the C-library?](https://igraph.discourse.group/t/is-make-line-graph-in-rigraph-the-same-as-in-mathematica-or-as-defined-in-the-c-library/1771)
**Author:** [@KeesP](https://igraph.discourse.group/u/KeesP)\ **Replies:** 3\ **Last updated:** [3 March 2024 10:48 UTC](https://igraph.discourse.group/t/is-make-line-graph-in-rigraph-the-same-as-in-mathematica-or-as-defined-in-the-c-library/1771 "2024-03-03T10:48:54Z")
Note that, library(igraph) g \<- graph(~ A--B) gll \<-make\_line\_graph(make\_line\_graph(g)) gives an empty graph. where I would expect g. See also: (1) https://igraph.org/c/pdf/latest/igraph-docs.pdf, page 651. (2) i… --- ## [igraph\_distances\_dijkstra](https://igraph.discourse.group/t/igraph-distances-dijkstra/1770)
**Author:** [@cyril](https://igraph.discourse.group/u/cyril)\ **Replies:** 2\ **Last updated:** [4 March 2024 09:26 UTC](https://igraph.discourse.group/t/igraph-distances-dijkstra/1770 "2024-03-04T09:26:13Z")
Hi, Is there a good way to call igraph C/C++ functions (e.g., igraph\_distances\_dijkstra) directly from C/C++ in our own package code? We have an application where we would like to calculate the shortest paths using the… --- ## [Adding a new community detection algorithm](https://igraph.discourse.group/t/adding-a-new-community-detection-algorithm/1657)
**Author:** [@DavidRConnell](https://igraph.discourse.group/u/DavidRConnell)\ **Replies:** 3\ **Last updated:** [21 February 2024 19:42 UTC](https://igraph.discourse.group/t/adding-a-new-community-detection-algorithm/1657 "2024-02-21T19:42:52Z")
Hi, I have been a part of developing a new community detection algorithm, SpeakEasy2 (SE2, currently under review for publication). It was originally written in matlab but for performance reasons, I have ported it to C u… --- ## [C/igraph 0.10.10](https://igraph.discourse.group/t/c-igraph-0-10-10/1750)
**Author:** [@szhorvat](https://igraph.discourse.group/u/szhorvat)\ **Replies:** 0\ **Last updated:** [13 February 2024 16:19 UTC](https://igraph.discourse.group/t/c-igraph-0-10-10/1750 "2024-02-13T16:19:28Z")
C/igraph 0.10.10 is now released. As usual, the source can be obtained from the GitHub releases page. This release includes a fix to a potentially impactful bug in testing whether a graph is a forest, and is therefore re… --- ## [C/igraph 0.10.9](https://igraph.discourse.group/t/c-igraph-0-10-9/1739)
**Author:** [@tamas](https://igraph.discourse.group/u/tamas)\ **Replies:** 0\ **Last updated:** [2 February 2024 15:34 UTC](https://igraph.discourse.group/t/c-igraph-0-10-9/1739 "2024-02-02T15:34:25Z")
C/igraph 0.10.9 is now released. As usual, the source can be obtained from the GitHub releases page. This is a maintenance release bringing multiple fixes, but also new experimental functions for checking whether a graph… --- ## [How to find cluster assignment of a node?](https://igraph.discourse.group/t/how-to-find-cluster-assignment-of-a-node/1724)
**Author:** [@wolfram77](https://igraph.discourse.group/u/wolfram77)\ **Replies:** 3\ **Last updated:** [18 December 2023 14:13 UTC](https://igraph.discourse.group/t/how-to-find-cluster-assignment-of-a-node/1724 "2023-12-18T14:13:15Z")
I am using the Leiden algorithm and trying to save the community membersip of each vertex to a file. Howerver i seem to get 1 as the community membership of all vertices in the graph. Should i use membership\[i\] instead o… --- ## [Cannot open include file: 'igraph\_version.h'](https://igraph.discourse.group/t/cannot-open-include-file-igraph-version-h/1717)
**Author:** [@David\_Cambre](https://igraph.discourse.group/u/David_Cambre)\ **Replies:** 3\ **Last updated:** [9 December 2023 12:07 UTC](https://igraph.discourse.group/t/cannot-open-include-file-igraph-version-h/1717 "2023-12-09T12:07:58Z")
Hello, I am struggling to implement iGraph in my Godot Module. (cpp project using SCons compiler) \`… fatal error C1083: Cannot open include file: ‘igraph\_version.h’: No such file or directory The include directory has … --- ## [the result is different neo4j for eigenvector\_centrality?](https://igraph.discourse.group/t/the-result-is-different-neo4j-for-eigenvector-centrality/1715)
**Author:** [@amwps290](https://igraph.discourse.group/u/amwps290)\ **Replies:** 2\ **Last updated:** [6 December 2023 00:55 UTC](https://igraph.discourse.group/t/the-result-is-different-neo4j-for-eigenvector-centrality/1715 "2023-12-06T00:55:47Z")
the cypher is: CREATE (home:Page {name:'Home'}), (about:Page {name:'About'}), (product:Page {name:'Product'}), (links:Page {name:'Links'}), (a:Page {name:'Site A'}), (b:Page {name:'Site B'}), (c:Page {name… --- ## [C/igraph 0.10.8](https://igraph.discourse.group/t/c-igraph-0-10-8/1704)
**Author:** [@szhorvat](https://igraph.discourse.group/u/szhorvat)\ **Replies:** 0\ **Last updated:** [17 November 2023 17:24 UTC](https://igraph.discourse.group/t/c-igraph-0-10-8/1704 "2023-11-17T17:24:45Z")
C/igraph 0.10.8 is now released. As usual, the source can be obtained from the GitHub releases page. This is a maintenance release bringing multiple fixes, compatibility improvements with Xcode 15, but also new experimen… --- ## [Question about gomory\_hu\_tree for multi-component graphs](https://igraph.discourse.group/t/question-about-gomory-hu-tree-for-multi-component-graphs/1678)
**Author:** [@Rob](https://igraph.discourse.group/u/Rob)\ **Replies:** 3\ **Last updated:** [29 September 2023 09:31 UTC](https://igraph.discourse.group/t/question-about-gomory-hu-tree-for-multi-component-graphs/1678 "2023-09-29T09:31:39Z")
Can the Graph().gomory\_hu\_tree() method be directly applied to an undirected graph with multiple components or do we have to run Graph().decompose() first to get a list of every connected component, then run Graph().gomo… --- ## [Linker command failed using igraph](https://igraph.discourse.group/t/linker-command-failed-using-igraph/1676)
**Author:** [@eromakh](https://igraph.discourse.group/u/eromakh)\ **Replies:** 1\ **Last updated:** [27 September 2023 19:31 UTC](https://igraph.discourse.group/t/linker-command-failed-using-igraph/1676 "2023-09-27T19:31:37Z")
Hi, I am new in igraph and C++ at all and I have a problem with linker. Igraph was installed successfully using Homebrew but when I tried to run the tutorial code tutorial1.c from examples tutorial1 on github I had an e… --- ## [C/igraph 0.10.7](https://igraph.discourse.group/t/c-igraph-0-10-7/1660)
**Author:** [@szhorvat](https://igraph.discourse.group/u/szhorvat)\ **Replies:** 0\ **Last updated:** [4 September 2023 15:20 UTC](https://igraph.discourse.group/t/c-igraph-0-10-7/1660 "2023-09-04T15:20:25Z")
C/igraph 0.10.7 is released today, incidentally exactly 4 years after the launch of this forum. As usual, the source can be obtained from the GitHub releases page. This is a maintenance release that brings bug fixes, do… --- ## [C/igraph 0.10.5](https://igraph.discourse.group/t/c-igraph-0-10-5/1602)
**Author:** [@szhorvat](https://igraph.discourse.group/u/szhorvat)\ **Replies:** 0\ **Last updated:** [29 June 2023 12:59 UTC](https://igraph.discourse.group/t/c-igraph-0-10-5/1602 "2023-06-29T12:59:11Z")
C/igraph 0.10.5 is now released. As usual, the source can be obtained from the GitHub releases page. This is a maintenance release bringing bug fixes, performance improvements, as well as new experimental features. See … --- ## [Setting and getting vertex attributes in C](https://igraph.discourse.group/t/setting-and-getting-vertex-attributes-in-c/1631)
**Author:** [@markrbower1](https://igraph.discourse.group/u/markrbower1)\ **Replies:** 2\ **Last updated:** [10 August 2023 17:52 UTC](https://igraph.discourse.group/t/setting-and-getting-vertex-attributes-in-c/1631 "2023-08-10T17:52:07Z")
This compiles and runs, but I cannot get the expected results: #include \ #include \ using namespace std; int main(int argc, char \*argv\[\]) { igraph\_vector\_int\_t gtypes, vtypes, etypes; … --- ## [Graph generator with the given weighted edge sequence.](https://igraph.discourse.group/t/graph-generator-with-the-given-weighted-edge-sequence/377)
**Author:** [@Alvaro\_Sechinel](https://igraph.discourse.group/u/Alvaro_Sechinel)\ **Replies:** 11\ **Last updated:** [21 July 2023 15:01 UTC](https://igraph.discourse.group/t/graph-generator-with-the-given-weighted-edge-sequence/377 "2023-07-21T15:01:58Z")
Hi, I need a graph generator similar to the: igraph\_degree\_sequence\_game — Generates a random graph with a given degree sequence But returns a random graph with the given weighted edge sequence. I have the weight of e… --- ## [Error installing libleidenalg package on a remote cluster. Probably really a question about cmake.](https://igraph.discourse.group/t/error-installing-libleidenalg-package-on-a-remote-cluster-probably-really-a-question-about-cmake/1608)
**Author:** [@markrbower1](https://igraph.discourse.group/u/markrbower1)\ **Replies:** 15\ **Last updated:** [8 July 2023 17:52 UTC](https://igraph.discourse.group/t/error-installing-libleidenalg-package-on-a-remote-cluster-probably-really-a-question-about-cmake/1608 "2023-07-08T17:52:13Z")
Because I’m on a remote cluster, I had to install igraph in my own directories: ${HOME}/igraph Now that I am installing the libleidenalg package, I need to tell cmake where the igraph .h files are located, but I cannot… --- ## [How to develop a sparse, weighted adjacency example?](https://igraph.discourse.group/t/how-to-develop-a-sparse-weighted-adjacency-example/1606)
**Author:** [@markrbower1](https://igraph.discourse.group/u/markrbower1)\ **Replies:** 5\ **Last updated:** [5 July 2023 14:02 UTC](https://igraph.discourse.group/t/how-to-develop-a-sparse-weighted-adjacency-example/1606 "2023-07-05T14:02:36Z")
I want to implement a graph in C with perhaps millions of vertices, but with local connectivity. A sparse matrix would be best to represent connections to an igraph constructor. I found the command “igraph\_sparse\_weighte… --- ## [Operations on igraph\_vector\_int\_t - membership](https://igraph.discourse.group/t/operations-on-igraph-vector-int-t-membership/1601)
**Author:** [@123AB](https://igraph.discourse.group/u/123AB)\ **Replies:** 0\ **Last updated:** [28 June 2023 01:43 UTC](https://igraph.discourse.group/t/operations-on-igraph-vector-int-t-membership/1601 "2023-06-28T01:43:34Z")
Hello, Recently I am trying to running the walktrap algorithm and get the membership of the walktrap algorithm result, but I do not know how to get each value of membership from igraph\_vector\_int\_t type. Basically I want… --- ## [How to convert c++ float\* datatype to igraph matrix datatype?](https://igraph.discourse.group/t/how-to-convert-c-float-datatype-to-igraph-matrix-datatype/1590)
**Author:** [@123AB](https://igraph.discourse.group/u/123AB)\ **Replies:** 4\ **Last updated:** [28 June 2023 01:36 UTC](https://igraph.discourse.group/t/how-to-convert-c-float-datatype-to-igraph-matrix-datatype/1590 "2023-06-28T01:36:18Z")
Hello, I got an error when I try to convert c++ float\* datatype to igraph\_real\_t. This is the error I got: error: cannot convert 'float\*' to 'igraph\_real\_t\* {aka double\*}' in assignment matrix\_data = data; The backgrou… --- ## [Operation on igraph\_vector\_t](https://igraph.discourse.group/t/operation-on-igraph-vector-t/1599)
**Author:** [@Pei\_Chang](https://igraph.discourse.group/u/Pei_Chang)\ **Replies:** 1\ **Last updated:** [26 June 2023 21:33 UTC](https://igraph.discourse.group/t/operation-on-igraph-vector-t/1599 "2023-06-26T21:33:04Z")
I’m recently switching the code from Python to C++, and now I encounter some problems on igraph\_vector\_t. In Python, if I want to randomly choose an element from a list, I just have to import a random package and type … --- ## [Errors installing igraph on a remote cluster](https://igraph.discourse.group/t/errors-installing-igraph-on-a-remote-cluster/1592)
**Author:** [@markrbower1](https://igraph.discourse.group/u/markrbower1)\ **Replies:** 9\ **Last updated:** [24 June 2023 21:02 UTC](https://igraph.discourse.group/t/errors-installing-igraph-on-a-remote-cluster/1592 "2023-06-24T21:02:47Z")
I am trying to install igraph in my personal account on the Bridges-2 cluster at the Pittsburgh Supercomputer Center (PSC). I have installed a recent version of “cmake” (cmake-3.20.0-linux-x86\_64) which calls an Nvidia … [Next page](https://igraph.discourse.group/tag/c/1.md?match_all_tags=true&page=1&tags%5B%5D=C)