Activity log for bug #1074402

Date Who What changed Old value New value Message
2012-11-02 15:50:04 Dimitris Diochnos bug added bug
2012-11-02 15:50:04 Dimitris Diochnos attachment added cliqueBug.tar.gz https://bugs.launchpad.net/bugs/1074402/+attachment/3421836/+files/cliqueBug.tar.gz
2012-11-02 16:10:38 Dimitris Diochnos description Might be related to this bug: https://bugs.launchpad.net/igraph/+bug/1073800 - igraph version: 0.6 Summary We load an undirected graph with self-loops. There is a very dense subgraph where there are many cliques (I do not know the exact number; I obtained this from a much larger dataset). Somehow, the self-loops trigger a bug. In the attached example I check one by one for the existence of all the edges among 12 nodes and all of them are part of the input (I have verified this by hand as well). However, the built-in functions for the size of the largest clique or the maximal cliques return different numbers when we include self-loops or not in the input. This is true both in C and in Python; I believe it is also true in R. Example: Input Description - 18 nodes, 133 edges, 8 self loops - Has a clique of size at least 12 - I do not know how many maximal cliques there are Attachment One source file in Python and two different input files with lists of edges. One of the files with the lists of edges includes self-loops, the other one does not. Example: Output $ ./cliques.py edgesSmall.txt IGRAPH U--- 18 133 -- ------------------------------------------------------- Checked 66 pairs among 12 nodes and 66 are neighbors ------------------------------------------------------- The size of the largest clique is 11 ------------------------------------------------------- There are 12 maximal cliques $ ./cliques.py edgesSmallNoLoops.txt IGRAPH U--- 18 125 -- ------------------------------------------------------- Checked 66 pairs among 12 nodes and 66 are neighbors ------------------------------------------------------- The size of the largest clique is 12 ------------------------------------------------------- There are 10 maximal cliques $ Might be related to this bug: https://bugs.launchpad.net/igraph/+bug/1073800 - igraph version: 0.6 Summary We load an undirected graph with self-loops. There is a very dense subgraph where there are many cliques (I do not know the exact number; I obtained this from a much larger dataset). Somehow, the self-loops trigger a bug. In the attached example I check one by one for the existence of all the edges among 12 nodes and all of them are part of the input (I have verified this by hand as well). However, the built-in functions for the size of the largest clique or the maximal cliques return different numbers when we include self-loops or not in the input. This is true both in C and in Python; I believe it is also true in R. Example: Input Description - 18 nodes, 133 edges, 8 self loops - Has a clique of size at least 12 among the nodes: [0, 3, 5, 6, 7, 9, 10, 11, 14, 15, 16, 17] - I do not know how many maximal cliques there are Example: Attachment One source file in Python and two different input files with lists of edges. One of the files with the lists of edges includes self-loops, the other one does not. Example: Output $ ./cliques.py edgesSmall.txt IGRAPH U--- 18 133 -- ------------------------------------------------------- Checked 66 pairs among 12 nodes and 66 are neighbors ------------------------------------------------------- The size of the largest clique is 11 ------------------------------------------------------- There are 12 maximal cliques $ ./cliques.py edgesSmallNoLoops.txt IGRAPH U--- 18 125 -- ------------------------------------------------------- Checked 66 pairs among 12 nodes and 66 are neighbors ------------------------------------------------------- The size of the largest clique is 12 ------------------------------------------------------- There are 10 maximal cliques $
2012-11-02 16:11:51 Dimitris Diochnos description Might be related to this bug: https://bugs.launchpad.net/igraph/+bug/1073800 - igraph version: 0.6 Summary We load an undirected graph with self-loops. There is a very dense subgraph where there are many cliques (I do not know the exact number; I obtained this from a much larger dataset). Somehow, the self-loops trigger a bug. In the attached example I check one by one for the existence of all the edges among 12 nodes and all of them are part of the input (I have verified this by hand as well). However, the built-in functions for the size of the largest clique or the maximal cliques return different numbers when we include self-loops or not in the input. This is true both in C and in Python; I believe it is also true in R. Example: Input Description - 18 nodes, 133 edges, 8 self loops - Has a clique of size at least 12 among the nodes: [0, 3, 5, 6, 7, 9, 10, 11, 14, 15, 16, 17] - I do not know how many maximal cliques there are Example: Attachment One source file in Python and two different input files with lists of edges. One of the files with the lists of edges includes self-loops, the other one does not. Example: Output $ ./cliques.py edgesSmall.txt IGRAPH U--- 18 133 -- ------------------------------------------------------- Checked 66 pairs among 12 nodes and 66 are neighbors ------------------------------------------------------- The size of the largest clique is 11 ------------------------------------------------------- There are 12 maximal cliques $ ./cliques.py edgesSmallNoLoops.txt IGRAPH U--- 18 125 -- ------------------------------------------------------- Checked 66 pairs among 12 nodes and 66 are neighbors ------------------------------------------------------- The size of the largest clique is 12 ------------------------------------------------------- There are 10 maximal cliques $ Might be related to this bug: https://bugs.launchpad.net/igraph/+bug/1073800 - igraph version: 0.6 Summary We load an undirected graph with self-loops. There is a very dense subgraph where there are many cliques (I do not know the exact number; I obtained this from a much larger dataset). Somehow, the self-loops trigger a bug. In the attached example I check one by one for the existence of all the edges among 12 nodes and all of them are part of the input (I have verified this by hand as well). However, the built-in functions for the size of the largest clique or the maximal cliques return different numbers when we include self-loops or not in the input. This is true both in C and in Python; I believe it is also true in R. Example: Input Description - 18 nodes, 133 edges, 8 self loops. - Has a clique of size at least 12 among the nodes:   [0, 3, 5, 6, 7, 9, 10, 11, 14, 15, 16, 17] - I do not know how many maximal cliques there are. Example: Attachment One source file in Python and two different input files with lists of edges. One of the files with the lists of edges includes self-loops, the other one does not. Example: Output $ ./cliques.py edgesSmall.txt IGRAPH U--- 18 133 -- ------------------------------------------------------- Checked 66 pairs among 12 nodes and 66 are neighbors ------------------------------------------------------- The size of the largest clique is 11 ------------------------------------------------------- There are 12 maximal cliques $ ./cliques.py edgesSmallNoLoops.txt IGRAPH U--- 18 125 -- ------------------------------------------------------- Checked 66 pairs among 12 nodes and 66 are neighbors ------------------------------------------------------- The size of the largest clique is 12 ------------------------------------------------------- There are 10 maximal cliques $
2012-11-02 19:23:49 Tamás Nepusz igraph: importance Undecided High
2012-11-02 19:23:51 Tamás Nepusz igraph: assignee Tamás Nepusz (ntamas)
2012-11-02 19:23:54 Tamás Nepusz igraph: status New In Progress
2012-11-02 19:23:56 Tamás Nepusz igraph: milestone 0.6.1
2012-11-02 19:30:31 Tamás Nepusz igraph: status In Progress Fix Committed
2013-03-03 20:44:19 Gábor Csárdi igraph: status Fix Committed Fix Released