Sorry. I am using Gcc 4.6.3 on a Ubuntu 12.04. Thanks,
Charles On Wed, Dec 5, 2012 at 10:01 PM, Gábor Csárdi <[email protected]> wrote: > Charles, > > what is your platform? OS, OS version, C compiler version? Anything else > that you might think is needed to reproduce this? > > G. > > > On Wed, Dec 5, 2012 at 3:44 PM, Charles Novaes de Santana > <[email protected]> wrote: >> >> Just to explay why I think my problem with the "infinity" values: >> >> Because I tryied to debug my program and I got the following message: >> >> Program received signal SIGSEGV, Segmentation fault. >> igraph_vector_fill (v=0xbffff6ac, e=inf) at vector.pmt:682 >> 682 *ptr = e; >> >> As the value received by function igraph_vector_fill is "e=inf" I >> suppose it was my problem. >> >> Best, >> >> Charles >> >> On Wed, Dec 5, 2012 at 9:40 PM, Charles Novaes de Santana >> <[email protected]> wrote: >> > Thank you again, Tamás. You were absolutely right about my mistake in >> > printing the matrix. I did a simple cast and my matrix operations >> > worked fine. >> > >> > But I still have problems with the "infinity" given by the >> > shortest_paths function. I did the function you suggested me (to >> > replace all IGRAPH_INFINITY by zeros), but I have problems in the >> > calculation of the shortest paths itself, before I have the >> > opportunity to replace the "inifinity" by "zero". >> > >> > If you don't mind, I am sending attached to this message a small >> > program with the part of my code where I got the error. And an example >> > of a network I am studying. Maybe it is an error in the format of my >> > network and I can not understand it yet. Or maybe it is because my >> > network is very sparse. >> > >> > Thank you very much for your attention, >> > >> > Best, >> > >> > Charles >> > >> > /*SOURCE CODE*/ >> > >> > #include<igraph.h> >> > >> > int main(void){ >> > igraph_t g1; >> > igraph_matrix_t l1; >> > igraph_vs_t vertices; >> > >> > int i,j; >> > FILE *ifile1; >> > >> > /*Reading the network*/ >> > ifile1=fopen("./network.net", "r"); >> > if (ifile1==0) {return 10;} >> > igraph_read_graph_pajek(&g1, ifile1); >> > fclose(ifile1); >> > >> > /*Initializing the matrix l1 and the vector of vertices*/ >> > >> > igraph_vs_all(&vertices); >> > igraph_matrix_init(&l1, 0, 0); >> > >> > /*Calculating the shortest paths*/ >> > >> > igraph_shortest_paths(&g1,&l1,vertices,vertices,IGRAPH_ALL); >> > >> > /*Desconstructors*/ >> > igraph_matrix_destroy(&l1); >> > igraph_vs_destroy(&vertices); >> > igraph_destroy(&g1); >> > return; >> > } >> > >> > >> > igraph_matrix_destroy(&l1); >> > igraph_vs_destroy(&vertices); >> > igraph_destroy(&g1); >> > >> > >> > On Wed, Dec 5, 2012 at 10:32 AM, Tamás Nepusz <[email protected]> wrote: >> >>> First, I was wondering if Igraph considers IGRAPH_INFINITY as zero or >> >>> as other value. >> >> IGRAPH_INFINITY is infinity, period. It is there only to provide us >> >> with a sort-of-platform-independent way to refer to infinity. >> >> >> >>> I am working with shortest-paths matrices and I would >> >>> like the distance between two vertices that can not reach each other >> >>> to be zero. >> >> Well, you have to check all the cells in the matrix and if a cell is >> >> equal to IGRAPH_INFINITY, you have to set it to zero. >> >> >> >>> (I tryied to do "igraph_matrix_scale(matrix,1./2)" and it gave >> >>> me a zero-matrix). >> >> Theoretically it should work; there is no limitation on >> >> igraph_matrix_scale to work on integer values only. I have just tested it >> >> on >> >> my machine and it worked for me, so I guess that the error is somewhere >> >> else; for instance, in the way you print the values. >> >> >> >> Cheers, >> >> -- >> >> T. >> >> >> >> >> >> _______________________________________________ >> >> igraph-help mailing list >> >> [email protected] >> >> https://lists.nongnu.org/mailman/listinfo/igraph-help >> > >> > >> > >> > -- >> > Um axé! :) >> > >> > -- >> > Charles Novaes de Santana >> > http://www.imedea.uib-csic.es/~charles >> > PhD student - Global Change >> > Laboratorio Internacional de Cambio Global >> > Department of Global Change Research >> > Instituto Mediterráneo de Estudios Avanzados(CSIC/UIB) >> > Calle Miquel Marques 21, 07190 >> > Esporles - Islas Baleares - España >> > >> > Office phone - +34 971 610 896 >> > Cell phone - +34 660 207 940 >> >> >> >> -- >> Um axé! :) >> >> -- >> Charles Novaes de Santana >> http://www.imedea.uib-csic.es/~charles >> PhD student - Global Change >> Laboratorio Internacional de Cambio Global >> Department of Global Change Research >> Instituto Mediterráneo de Estudios Avanzados(CSIC/UIB) >> Calle Miquel Marques 21, 07190 >> Esporles - Islas Baleares - España >> >> Office phone - +34 971 610 896 >> Cell phone - +34 660 207 940 >> >> _______________________________________________ >> igraph-help mailing list >> [email protected] >> https://lists.nongnu.org/mailman/listinfo/igraph-help > > > > > -- > Gabor Csardi <[email protected]> MTA KFKI RMKI > > > _______________________________________________ > igraph-help mailing list > [email protected] > https://lists.nongnu.org/mailman/listinfo/igraph-help > -- Um axé! :) -- Charles Novaes de Santana http://www.imedea.uib-csic.es/~charles PhD student - Global Change Laboratorio Internacional de Cambio Global Department of Global Change Research Instituto Mediterráneo de Estudios Avanzados(CSIC/UIB) Calle Miquel Marques 21, 07190 Esporles - Islas Baleares - España Office phone - +34 971 610 896 Cell phone - +34 660 207 940 _______________________________________________ igraph-help mailing list [email protected] https://lists.nongnu.org/mailman/listinfo/igraph-help
