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/* -*- mode: C -*- */
/*
IGraph library.
Copyright (C) 2006-2012 Gabor Csardi <csardi.gabor@gmail.com>
334 Harvard st, Cambridge MA, 02139 USA
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
02110-1301 USA
*/
#include <igraph.h>
#include <stdlib.h>
void print_vector(igraph_vector_t *v) {
long int i, l=igraph_vector_size(v);
for (i=0; i<l; i++) {
printf(" %li", (long int) VECTOR(*v)[i]);
}
printf("\n");
}
int check_evecs(const igraph_t *graph, const igraph_vector_ptr_t *vecs,
const igraph_vector_ptr_t *evecs, int error_code) {
igraph_bool_t directed=igraph_is_directed(graph);
long int i, n=igraph_vector_ptr_size(vecs);
if (igraph_vector_ptr_size(evecs) != n) { exit(error_code+1); }
for (i=0; i<n; i++) {
igraph_vector_t *vvec=VECTOR(*vecs)[i];
igraph_vector_t *evec=VECTOR(*evecs)[i];
long int j, n2=igraph_vector_size(evec);
if (igraph_vector_size(vvec) == 0 && n2==0) { continue; }
if (igraph_vector_size(vvec) != n2+1) { exit(error_code+2); }
for (j=0; j<n2; j++) {
long int edge=VECTOR(*evec)[j];
long int from=VECTOR(*vvec)[j];
long int to=VECTOR(*vvec)[j+1];
if (directed) {
if (from != IGRAPH_FROM(graph, edge) ||
to != IGRAPH_TO (graph, edge)) {
exit(error_code);
}
} else {
long int from2=IGRAPH_FROM(graph, edge);
long int to2=IGRAPH_TO(graph, edge);
long int min1= from < to ? from : to;
long int max1= from < to ? to : from;
long int min2= from2 < to2 ? from2 : to2;
long int max2= from2 < to2 ? to2 : from2;
if (min1 != min2 || max1 != max2) { exit(error_code+3); }
}
}
}
return 0;
}
int check_pred_inbound(const igraph_t* graph, const igraph_vector_long_t* pred,
const igraph_vector_long_t* inbound, int start, int error_code) {
long int i, n = igraph_vcount(graph);
if (igraph_vector_long_size(pred) != n ||
igraph_vector_long_size(inbound) != n) {
exit(error_code);
}
if (VECTOR(*pred)[start] != start || VECTOR(*inbound)[start] != -1)
exit(error_code+1);
for (i = 0; i < n; i++) {
if (VECTOR(*pred)[i] == -1) {
if (VECTOR(*inbound)[i] != -1) {
exit(error_code+2);
}
} else if (VECTOR(*pred)[i] == i) {
if (i != start) {
exit(error_code+3);
}
if (VECTOR(*inbound)[i] != -1) {
exit(error_code+4);
}
} else {
long int eid = VECTOR(*inbound)[i];
long int u = IGRAPH_FROM(graph, eid), v = IGRAPH_TO(graph, eid);
if (v != i && !igraph_is_directed(graph)) {
long int dummy = u;
u = v; v = dummy;
}
if (v != i) {
exit(error_code+5);
} else if (u != VECTOR(*pred)[i]) {
exit(error_code+6);
}
}
}
return 0;
}
int main() {
igraph_t g;
igraph_vector_ptr_t vecs, evecs;
igraph_vector_long_t pred, inbound;
long int i;
igraph_real_t weights[] = { 1, 2, 3, 4, 5, 1, 1, 1, 1, 1 };
igraph_real_t weights2[] = { 0,2,1, 0,5,2, 1,1,0, 2,2,8, 1,1,3, 1,1,4, 2,1 };
igraph_vector_t weights_vec;
igraph_vs_t vs;
/* Simple ring graph without weights */
igraph_ring(&g, 10, IGRAPH_UNDIRECTED, 0, 1);
igraph_vector_ptr_init(&vecs, 5);
igraph_vector_ptr_init(&evecs, 5);
igraph_vector_long_init(&pred, 0);
igraph_vector_long_init(&inbound, 0);
for (i=0; i<igraph_vector_ptr_size(&vecs); i++) {
VECTOR(vecs)[i] = calloc(1, sizeof(igraph_vector_t));
igraph_vector_init(VECTOR(vecs)[i], 0);
VECTOR(evecs)[i] = calloc(1, sizeof(igraph_vector_t));
igraph_vector_init(VECTOR(evecs)[i], 0);
}
igraph_vs_vector_small(&vs, 1, 3, 5, 2, 1, -1);
igraph_get_shortest_paths_dijkstra(&g, /*vertices=*/ &vecs,
/*edges=*/ &evecs, /*from=*/ 0, /*to=*/ vs,
/*weights=*/ 0, /*mode=*/ IGRAPH_OUT,
/*predecessors=*/ &pred,
/*inbound_edges=*/ &inbound);
check_evecs(&g, &vecs, &evecs, 10);
check_pred_inbound(&g, &pred, &inbound, /* from= */ 0, 40);
for (i=0; i<igraph_vector_ptr_size(&vecs); i++) {
print_vector(VECTOR(vecs)[i]);
}
/* Same ring, but with weights */
igraph_vector_view(&weights_vec, weights, sizeof(weights)/sizeof(igraph_real_t));
igraph_get_shortest_paths_dijkstra(&g, /*vertices=*/ &vecs,
/*edges=*/ &evecs, /*from=*/ 0, /*to=*/ vs,
&weights_vec, IGRAPH_OUT,
/*predecessors=*/ &pred,
/*inbound_edges=*/ &inbound);
check_evecs(&g, &vecs, &evecs, 20);
check_pred_inbound(&g, &pred, &inbound, /* from= */ 0, 50);
for (i=0; i<igraph_vector_ptr_size(&vecs); i++) {
print_vector(VECTOR(vecs)[i]);
}
igraph_destroy(&g);
/* More complicated example */
igraph_small(&g, 10, IGRAPH_DIRECTED,
0,1, 0,2, 0,3, 1,2, 1,4, 1,5,
2,3, 2,6, 3,2, 3,6,
4,5, 4,7, 5,6, 5,8, 5,9,
7,5, 7,8, 8,9,
5,2,
2,1,
-1);
igraph_vector_view(&weights_vec, weights2, sizeof(weights2)/sizeof(igraph_real_t));
igraph_get_shortest_paths_dijkstra(&g, /*vertices=*/ &vecs,
/*edges=*/ &evecs, /*from=*/ 0, /*to=*/ vs,
&weights_vec, IGRAPH_OUT,
/*predecessors=*/ &pred,
/*inbound_edges=*/ &inbound);
check_evecs(&g, &vecs, &evecs, 30);
check_pred_inbound(&g, &pred, &inbound, /* from= */ 0, 60);
for (i=0; i<igraph_vector_ptr_size(&vecs); i++) {
print_vector(VECTOR(vecs)[i]);
igraph_vector_destroy(VECTOR(vecs)[i]);
free(VECTOR(vecs)[i]);
igraph_vector_destroy(VECTOR(evecs)[i]);
free(VECTOR(evecs)[i]);
}
igraph_vector_ptr_destroy(&vecs);
igraph_vector_ptr_destroy(&evecs);
igraph_vector_long_destroy(&pred);
igraph_vector_long_destroy(&inbound);
igraph_vs_destroy(&vs);
igraph_destroy(&g);
if (!IGRAPH_FINALLY_STACK_EMPTY) return 1;
return 0;
}
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