/*
* graph_neighbor_subgraph - calculate the @subgraph consists of the neighbors of vertex @s
* used for calculate the local efficiency.
*
* @neis: neighbors' id
*/
int graph_neighbor_subgraph(const graph_t *graph, graph_t *subgraph, vector_int *neis, int s, graph_neimode_t mode)
{
int vc = graph_vertices_count(graph);
graph_neighbors(graph, neis, s, mode);
vector_int edges;
vector_int_init(&edges, 0);
vector_int neis2;
vector_int_init(&neis2, 0);
int v, w;
for (int i = 0; i < vector_int_size(neis); i++) {
v = VECTOR(*neis)[i];
if (v == s) continue;
graph_neighbors(graph, &neis2, v, GRAPH_OUT);
for (int j = 0; j < vector_int_size(&neis2); j++) {
w = VECTOR(neis2)[j];
if (w == s || w == v) continue;
int wid = vector_int_whereis(neis, w);
if (-1 != wid) {
vector_int_push_back(&edges, i);
vector_int_push_back(&edges, wid);
}
}
}
new_graph(subgraph, &edges, vector_int_size(neis), graph_is_directed(graph));
vector_int_destroy(&neis2);
vector_int_destroy(&edges);
return 0;
}
/*
* graph_has_multiple
*/
int graph_has_multiple(const graph_t *graph)
{
int vc = graph_vertices_count(graph);
int ec = graph_edges_count(graph);
int dflag = graph_is_directed(graph);
if (vc == 0 || ec == 0)
return 0;
vector_int neis;
vector_int_init(&neis, 0);
int found = 0, n;
for (int i = 0; i < vc && !found; i++) {
graph_neighbors(graph, &neis, i, GRAPH_OUT);
n = vector_int_size(&neis);
for (int j = 1; j < n; j++) {
if (VECTOR(neis)[j-1] == VECTOR(neis)[j]) {
if (dflag)
/* Directed, so this is a real multiple edge */
return 1;
else if (VECTOR(neis)[j-1] != i)
/* Undirected, but not a loop edge */
return 1;
else if (j < n-1 && VECTOR(neis)[j] == VECTOR(neis)[j+1])
/* Undirected, loop edge, multiple times */
return 1;
}
}
}
return 0;
}
/*
* graph_edge
*/
int graph_edge(const graph_t *graph, int eid, int *from, int *to)
{
*from = VECTOR(graph->from)[eid];
*to = VECTOR(graph->to)[eid];
if (!graph_is_directed(graph) && *from > *to) {
int tmp = *from;
*from = *to;
*to = tmp;
}
return 0;
}
void _meta(graph_t *g) {
uint32_t i;
uint16_t nmsgs;
char *msg;
nmsgs = graph_log_num_msgs(g);
printf("num nodes: %u\n", graph_num_nodes(g));
printf("num edges: %u\n", graph_num_edges(g));
printf("directed: %u\n", graph_is_directed(g));
printf("log messages:\n");
for (i = 0; i < nmsgs; i++) {
msg = graph_log_get_msg(g, i);
printf(" %3u: %s\n", i, msg);
}
}
int graph_subgraph(const graph_t *graph, graph_t *subgraph, graph_vs_t vids)
{
int vc = graph_vertices_count(graph);
int ec = graph_edges_count(graph);
vector_int vss;
vector_int_init(&vss, vc);
vector_int_fill(&vss, -1);
int i,j,u,v;
graph_vit_t vit;
graph_vit_create(graph, vids, &vit);
int nvc = GRAPH_VIT_SIZE(vit);
for (GRAPH_VIT_RESET(vit), i=0; !GRAPH_VIT_END(vit); GRAPH_VIT_NEXT(vit), i++) {
int vid = GRAPH_VIT_GET(vit);
VECTOR(vss)[vid] = i;
}
graph_vit_destroy(&vit);
int nec = 0;
vector_int new_edges;
vector_int_init(&new_edges, 2 * ec);
for (int eid = 0; eid < ec; eid++) {
graph_edge(graph, eid, &i, &j);
u = VECTOR(vss)[i];
v = VECTOR(vss)[j];
if (-1 == u || -1 == v)
continue;
VECTOR(new_edges)[2*nec+0] = u;
VECTOR(new_edges)[2*nec+1] = v;
nec++;
}
vector_int_resize(&new_edges, 2 * nec);
new_graph(subgraph, &new_edges, nvc, graph_is_directed(graph));
vector_int_destroy(&new_edges);
vector_int_destroy(&vss);
return 0;
}
