[igraph] (no subject)

[Anselmo Garcia Cantu Ros]

Hi, 

I am debuting in igraph and am using c igraph 0.6.
I need to calculate distances within weighted graphs. Thus I've built the 
graph from a weighted adjacency matrix, and then used 
igraph_shortest_paths_dijkstra(). Everything was fine until working with 
graph sizes of the order 10^4: Out of memory (apparently, the size was too 
big for matrix). To overcome this situation I decided to build up the 
graphs from a 3-column adjacency list (in format .ncol), that was fed into 
"igraph_read_graph_ncol()". The edge query was done again using 
igraph_cattribute_EANV(). When executing I get: 

"Error at cattributes.c:1915 :Unknown attribute, Invalid value" 

Please help me. The code is the following: 

#include <igraph/igraph.h>
#include <stdio.h>
int main(void) {
            FILE *fp;
	    fp=fopen("Matrixoutweight.ncol","r"); 

	igraph_i_set_attribute_table(&igraph_cattribute_table);	 

  igraph_t graph;

  int i,j,nedges,nertex;
  float test;
  const char weight;	 

igraph_read_graph_ncol(&graph,fp,NULL,0,1,0); 

        nedges=igraph_ecount(&graph);
	nertex=igraph_vcount(&graph); 

           igraph_vector_t weightatt;
           igraph_vector_init(&weightatt,nedges);
           igraph_matrix_t SP;
          igraph_matrix_init(&SP,nertex,nertex);	 

        
igraph_cattribute_EANV(&graph,&weight,igraph_ess_all(IGRAPH_EDGEORDER_FROM)
, &weightatt);
                
        
        
igraph_shortest_paths_dijkstra(&graph,&SP,igraph_vss_all(),igraph_vss_all()
,&weightatt,IGRAPH_OUT); 

         for (i = 0; i < nertex ; i++)
                {
                        for (j = 0; j < nertex; j++)
                                {
                                test=igraph_matrix_e(&SP,i,j);
                                printf("%d %d %f\n",i,j,test);
                                }
                }
        
        igraph_destroy(&graph);
        igraph_vector_destroy(&weightatt);
        igraph_matrix_destroy(&SP);
                
       fclose(fp);
        
 return 0;
} 

Thanks in advance