static int
countComponents(Agraph_t *g, int* max_degree, float *nontree_frac)
{
int nc = 0;
int sum_edges = 0;
int sum_nontree = 0;
int deg;
int n_edges;
int n_nodes;
Agnode_t* n;
for (n = agfstnode(g); n; n = agnxtnode(n)) {
if (!getval(n)) {
nc++;
n_edges = 0;
n_nodes = label(n,0,&n_edges);
sum_edges += n_edges;
sum_nontree += (n_edges - n_nodes + 1);
}
}
if (max_degree) {
int maxd = 0;
for (n = agfstnode(g); n; n = agnxtnode(n)) {
deg = agdegree(n,TRUE,TRUE);
if (maxd < deg) maxd = deg;
setval(n,0);
}
*max_degree = maxd;
}
if (nontree_frac) {
if (sum_edges > 0) *nontree_frac = (float)sum_nontree / (float)sum_edges;
else *nontree_frac = 0.0;
}
return nc;
}
int agnedges(Agraph_t * g)
{
Agnode_t *n;
int rv = 0;
for (n = agfstnode(g); n; n = agnxtnode(n))
rv += agdegree(n, FALSE, TRUE); /* must use OUT to get self-arcs */
return rv;
}
/*-------------------------------------------------------------------------*\
* Write info about a node to stdout.
* Example:
* n:info()
\*-------------------------------------------------------------------------*/
static int gr_info(lua_State *L)
{
Agraph_t *g;
gr_node_t *ud = tonode(L, 1, STRICT);
Agedge_t *se;
Agsym_t *sym;
g = agraphof(ud->n);
printf("INFO NODE '%s' '%s' id=%lu seq=%d\n", agnameof(ud->n), ud->name, (unsigned long) AGID(ud->n), AGSEQ(ud->n));
printf(" ptr: %p\n", ud->n);
printf(" Symbols:\n");
se = agfstout(g, ud->n);
sym=0;
while ((sym = agnxtattr(g,AGNODE,sym))!=NULL)
printf(" %s = '%s'\n",sym->name,sym->defval);
#if 0
printf(" Out edges: d-out=%d u-out=%d\n", agdegree(g, ud->n, 0, 1), agcountuniqedges(g, ud->n, 0, 1));
#endif
while (se) {
printf(" name: '%s', head: '%s', tail: '%s' id=%lud, seq=%d %p\n",
agnameof(se), agnameof(aghead(se)), agnameof(agtail(se)), (unsigned long) AGID(se), AGSEQ(se), (void*)se);
se = agnxtout(g, se);
}
#if 0
printf(" In edges: d-in=%d u-in=%d\n", agdegree(g, ud->n, 1, 0), agcountuniqedges(g, ud->n, 1, 0));
#endif
se = agfstin(g, ud->n);
while (se) {
printf(" name: '%s', head: '%s', tail: '%s' îd=%lu seq=%d %p\n",
agnameof(se), agnameof(aghead(se)), agnameof(agtail(se)), (unsigned long) AGID(se), AGSEQ(se), (void*)se);
se = agnxtin(g, se);
}
#if 0
printf(" Edges: d-io=%d u-io=%d\n", agdegree(g, ud->n, 1, 1), agcountuniqedges(g, ud->n, 1, 1));
#endif
se = agfstedge(g, ud->n);
while (se) {
printf(" name: '%s', head: '%s', tail: '%s' id=%lud seq=%d %p\n",
agnameof(se), agnameof(aghead(se)), agnameof(agtail(se)), (unsigned long) AGID(se), AGSEQ(se), (void*)se);
se = agnxtedge(g, se, ud->n);
}
return 0;
}
static int visit(Agnode_t * n, Agraph_t * map, Stack * sp, sccstate * st)
{
unsigned int m, min;
Agnode_t *t;
Agraph_t *subg;
Agedge_t *e;
min = ++(st->ID);
setval(n, min);
push(sp, n);
#ifdef USE_CGRAPH
for (e = agfstout(n->root, n); e; e = agnxtout(n->root, e)) {
#else
for (e = agfstout(n); e; e = agnxtout(e)) {
#endif
t = aghead(e);
if (getval(t) == 0)
m = visit(t, map, sp, st);
else
m = getval(t);
if (m < min)
min = m;
}
if (getval(n) == min) {
if (!wantDegenerateComp && (top(sp) == n)) {
setval(n, INF);
pop(sp);
} else {
char name[32];
Agraph_t *G = agraphof(n);;
sprintf(name, "cluster_%d", (st->Comp)++);
subg = agsubg(G, name, TRUE);
agbindrec(subg, "scc_graph", sizeof(Agraphinfo_t), TRUE);
setrep(subg, agnode(map, name, TRUE));
do {
t = pop(sp);
agsubnode(subg, t, TRUE);
setval(t, INF);
setscc(t, subg);
st->N_nodes_in_nontriv_SCC++;
} while (t != n);
#ifdef USE_CGRAPH
nodeInduce(subg, map);
#else
nodeInduce(subg);
#endif
if (!Silent)
agwrite(subg, stdout);
}
}
return min;
}
static int label(Agnode_t * n, int nodecnt, int *edgecnt)
{
Agedge_t *e;
setval(n, 1);
nodecnt++;
#ifdef USE_CGRAPH
for (e = agfstedge(n->root, n); e; e = agnxtedge(n->root, e, n)) {
#else
for (e = agfstedge(n); e; e = agnxtedge(e, n)) {
#endif
(*edgecnt) += 1;
if (e->node == n)
e = agopp(e);
if (!getval(e->node))
nodecnt = label(e->node, nodecnt, edgecnt);
}
return nodecnt;
}
static int
countComponents(Agraph_t * g, int *max_degree, float *nontree_frac)
{
int nc = 0;
int sum_edges = 0;
int sum_nontree = 0;
int deg;
int n_edges;
int n_nodes;
Agnode_t *n;
#ifdef USE_CGRAPH
for (n = agfstnode(g); n; n = agnxtnode(g, n)) {
#else
for (n = agfstnode(g); n; n = agnxtnode(n)) {
#endif
if (!getval(n)) {
nc++;
n_edges = 0;
n_nodes = label(n, 0, &n_edges);
sum_edges += n_edges;
sum_nontree += (n_edges - n_nodes + 1);
}
}
if (max_degree) {
int maxd = 0;
#ifdef USE_CGRAPH
for (n = agfstnode(g); n; n = agnxtnode(g, n)) {
deg = agdegree(g, n, TRUE, TRUE);
#else
for (n = agfstnode(g); n; n = agnxtnode(n)) {
deg = agdegree(n, TRUE, TRUE);
#endif
if (maxd < deg)
maxd = deg;
setval(n, 0);
}
*max_degree = maxd;
}
if (nontree_frac) {
if (sum_edges > 0)
*nontree_frac = (float) sum_nontree / (float) sum_edges;
else
*nontree_frac = 0.0;
}
return nc;
}
static void process(Agraph_t * G)
{
Agnode_t *n;
Agraph_t *map;
int nc = 0;
float nontree_frac = 0;
int Maxdegree = 0;
Stack stack;
sccstate state;
aginit(G, AGRAPH, "scc_graph", sizeof(Agraphinfo_t), TRUE);
aginit(G, AGNODE, "scc_node", sizeof(Agnodeinfo_t), TRUE);
state.Comp = state.ID = 0;
state.N_nodes_in_nontriv_SCC = 0;
if (Verbose)
nc = countComponents(G, &Maxdegree, &nontree_frac);
initStack(&stack, agnnodes(G) + 1);
map = agopen("scc_map", Agdirected, (Agdisc_t *) 0);
#ifdef USE_CGRAPH
for (n = agfstnode(G); n; n = agnxtnode(G, n))
#else
for (n = agfstnode(G); n; n = agnxtnode(n))
#endif
if (getval(n) == 0)
visit(n, map, &stack, &state);
freeStack(&stack);
if (!Silent)
agwrite(map, stdout);
agclose(map);
if (Verbose)
fprintf(stderr, "%d %d %d %d %.4f %d %.4f\n",
agnnodes(G), agnedges(G), nc, state.Comp,
state.N_nodes_in_nontriv_SCC / (double) agnnodes(G),
Maxdegree, nontree_frac);
else
fprintf(stderr, "%d nodes, %d edges, %d strong components\n",
agnnodes(G), agnedges(G), state.Comp);
}
static char *useString = "Usage: %s [-sdv?] <files>\n\
-s - silent\n\
-d - allow degenerate components\n\
-v - verbose\n\
-? - print usage\n\
If no files are specified, stdin is used\n";
static void usage(int v)
{
printf(useString, CmdName);
exit(v);
}
static int myindegree(Agnode_t *n)
{
return agdegree(n->root, n, TRUE, FALSE);
}
