openfoam/applications/utilities/parallelProcessing/decompositionMethods/metis-5.0pre2/libmetis/match.c
2008-04-15 18:56:58 +01:00

268 lines
6.8 KiB
C

/*
* Copyright 1997, Regents of the University of Minnesota
*
* match.c
*
* This file contains the code that computes matchings and creates the next
* level coarse graph.
*
* Started 7/23/97
* George
*
* $Id: match.c,v 1.3 2003/07/31 15:49:43 karypis Exp $
*
*/
#include <metislib.h>
/*************************************************************************
* This function finds a matching using the HEM heuristic
**************************************************************************/
void Match_RM(CtrlType *ctrl, GraphType *graph)
{
idxtype i, ii, j, nvtxs, cnvtxs, maxidx;
idxtype *xadj, *vwgt, *adjncy, *adjwgt;
idxtype *match, *cmap, *perm;
IFSET(ctrl->dbglvl, DBG_TIME, gk_startcputimer(ctrl->MatchTmr));
nvtxs = graph->nvtxs;
xadj = graph->xadj;
vwgt = graph->vwgt;
adjncy = graph->adjncy;
adjwgt = graph->adjwgt;
cmap = graph->cmap;
match = idxset(nvtxs, UNMATCHED, idxwspacemalloc(ctrl, nvtxs));
perm = idxwspacemalloc(ctrl, nvtxs);
RandomPermute(nvtxs, perm, 1);
cnvtxs = 0;
for (ii=0; ii<nvtxs; ii++) {
i = perm[ii];
if (match[i] == UNMATCHED) { /* Unmatched */
maxidx = i;
/* Find a random matching, subject to maxvwgt constraints */
for (j=xadj[i]; j<xadj[i+1]; j++) {
if (match[adjncy[j]] == UNMATCHED && vwgt[i]+vwgt[adjncy[j]] <= ctrl->maxvwgt) {
maxidx = adjncy[j];
break;
}
}
cmap[i] = cmap[maxidx] = cnvtxs++;
match[i] = maxidx;
match[maxidx] = i;
}
}
IFSET(ctrl->dbglvl, DBG_TIME, gk_stopcputimer(ctrl->MatchTmr));
CreateCoarseGraph(ctrl, graph, cnvtxs, match, perm);
idxwspacefree(ctrl, nvtxs);
idxwspacefree(ctrl, nvtxs);
}
/*************************************************************************
* This function finds a matching using the HEM heuristic
**************************************************************************/
void Match_RM_NVW(CtrlType *ctrl, GraphType *graph)
{
idxtype i, ii, j, nvtxs, cnvtxs, maxidx;
idxtype *xadj, *adjncy;
idxtype *match, *cmap, *perm;
IFSET(ctrl->dbglvl, DBG_TIME, gk_startcputimer(ctrl->MatchTmr));
nvtxs = graph->nvtxs;
xadj = graph->xadj;
adjncy = graph->adjncy;
cmap = graph->cmap;
match = idxset(nvtxs, UNMATCHED, idxwspacemalloc(ctrl, nvtxs));
perm = idxwspacemalloc(ctrl, nvtxs);
RandomPermute(nvtxs, perm, 1);
cnvtxs = 0;
for (ii=0; ii<nvtxs; ii++) {
i = perm[ii];
if (match[i] == UNMATCHED) { /* Unmatched */
maxidx = i;
/* Find a random matching, subject to maxvwgt constraints */
for (j=xadj[i]; j<xadj[i+1]; j++) {
if (match[adjncy[j]] == UNMATCHED) {
maxidx = adjncy[j];
break;
}
}
cmap[i] = cmap[maxidx] = cnvtxs++;
match[i] = maxidx;
match[maxidx] = i;
}
}
IFSET(ctrl->dbglvl, DBG_TIME, gk_stopcputimer(ctrl->MatchTmr));
CreateCoarseGraph_NVW(ctrl, graph, cnvtxs, match, perm);
idxwspacefree(ctrl, nvtxs);
idxwspacefree(ctrl, nvtxs);
}
/*************************************************************************
* This function finds a matching using the HEM heuristic
**************************************************************************/
void Match_HEM(CtrlType *ctrl, GraphType *graph)
{
idxtype i, ii, j, k, nvtxs, cnvtxs, maxidx, maxwgt;
idxtype *xadj, *vwgt, *adjncy, *adjwgt;
idxtype *match, *cmap, *perm;
IFSET(ctrl->dbglvl, DBG_TIME, gk_startcputimer(ctrl->MatchTmr));
nvtxs = graph->nvtxs;
xadj = graph->xadj;
vwgt = graph->vwgt;
adjncy = graph->adjncy;
adjwgt = graph->adjwgt;
cmap = graph->cmap;
match = idxset(nvtxs, UNMATCHED, idxwspacemalloc(ctrl, nvtxs));
perm = idxwspacemalloc(ctrl, nvtxs);
RandomPermute(nvtxs, perm, 1);
cnvtxs = 0;
for (ii=0; ii<nvtxs; ii++) {
i = perm[ii];
if (match[i] == UNMATCHED) { /* Unmatched */
maxidx = i;
maxwgt = 0;
/* Find a heavy-edge matching, subject to maxvwgt constraints */
for (j=xadj[i]; j<xadj[i+1]; j++) {
k = adjncy[j];
if (match[k] == UNMATCHED && maxwgt < adjwgt[j] && vwgt[i]+vwgt[k] <= ctrl->maxvwgt) {
maxwgt = adjwgt[j];
maxidx = adjncy[j];
}
}
cmap[i] = cmap[maxidx] = cnvtxs++;
match[i] = maxidx;
match[maxidx] = i;
}
}
IFSET(ctrl->dbglvl, DBG_TIME, gk_stopcputimer(ctrl->MatchTmr));
CreateCoarseGraph(ctrl, graph, cnvtxs, match, perm);
idxwspacefree(ctrl, nvtxs);
idxwspacefree(ctrl, nvtxs);
}
/*************************************************************************
* This function finds a matching using the HEM heuristic
**************************************************************************/
void Match_SHEM(CtrlType *ctrl, GraphType *graph)
{
idxtype i, ii, j, k, nvtxs, cnvtxs, maxidx, maxwgt, avgdegree;
idxtype *xadj, *vwgt, *adjncy, *adjwgt;
idxtype *match, *cmap, *degrees, *perm, *tperm;
IFSET(ctrl->dbglvl, DBG_TIME, gk_startcputimer(ctrl->MatchTmr));
nvtxs = graph->nvtxs;
xadj = graph->xadj;
vwgt = graph->vwgt;
adjncy = graph->adjncy;
adjwgt = graph->adjwgt;
cmap = graph->cmap;
match = idxset(nvtxs, UNMATCHED, idxwspacemalloc(ctrl, nvtxs));
perm = idxwspacemalloc(ctrl, nvtxs);
tperm = idxwspacemalloc(ctrl, nvtxs);
degrees = idxwspacemalloc(ctrl, nvtxs);
RandomPermute(nvtxs, tperm, 1);
avgdegree = 0.7*(xadj[nvtxs]/nvtxs);
for (i=0; i<nvtxs; i++)
degrees[i] = (xadj[i+1]-xadj[i] > avgdegree ? avgdegree : xadj[i+1]-xadj[i]);
BucketSortKeysInc(nvtxs, avgdegree, degrees, tperm, perm);
cnvtxs = 0;
/* Take care any islands. Islands are matched with non-islands due to coarsening */
for (ii=0; ii<nvtxs; ii++) {
i = perm[ii];
if (match[i] == UNMATCHED) { /* Unmatched */
if (xadj[i] < xadj[i+1])
break;
maxidx = i;
for (j=nvtxs-1; j>ii; j--) {
k = perm[j];
if (match[k] == UNMATCHED && xadj[k] < xadj[k+1]) {
maxidx = k;
break;
}
}
cmap[i] = cmap[maxidx] = cnvtxs++;
match[i] = maxidx;
match[maxidx] = i;
}
}
/* Continue with normal matching */
for (; ii<nvtxs; ii++) {
i = perm[ii];
if (match[i] == UNMATCHED) { /* Unmatched */
maxidx = i;
maxwgt = 0;
/* Find a heavy-edge matching, subject to maxvwgt constraints */
for (j=xadj[i]; j<xadj[i+1]; j++) {
if (match[adjncy[j]] == UNMATCHED && maxwgt < adjwgt[j] && vwgt[i]+vwgt[adjncy[j]] <= ctrl->maxvwgt) {
maxwgt = adjwgt[j];
maxidx = adjncy[j];
}
}
cmap[i] = cmap[maxidx] = cnvtxs++;
match[i] = maxidx;
match[maxidx] = i;
}
}
IFSET(ctrl->dbglvl, DBG_TIME, gk_stopcputimer(ctrl->MatchTmr));
idxwspacefree(ctrl, nvtxs); /* degrees */
idxwspacefree(ctrl, nvtxs); /* tperm */
CreateCoarseGraph(ctrl, graph, cnvtxs, match, perm);
idxwspacefree(ctrl, nvtxs);
idxwspacefree(ctrl, nvtxs);
}