/*************************************************************************
* This function takes a graph and produces a bisection of it
**************************************************************************/
int MlevelVolKWayPartitioning(CtrlType *ctrl, GraphType *graph, int nparts, idxtype *part,
float *tpwgts, float ubfactor)
{
GraphType *cgraph;
int wgtflag=3, numflag=0, options[10], edgecut;
cgraph = Coarsen2Way(ctrl, graph);
IFSET(ctrl->dbglvl, DBG_TIME, starttimer(ctrl->InitPartTmr));
AllocateVolKWayPartitionMemory(ctrl, cgraph, nparts);
options[0] = 1;
options[OPTION_CTYPE] = MATCH_SHEMKWAY;
options[OPTION_ITYPE] = IPART_GGPKL;
options[OPTION_RTYPE] = RTYPE_FM;
options[OPTION_DBGLVL] = 0;
METIS_WPartGraphRecursive(&cgraph->nvtxs, cgraph->xadj, cgraph->adjncy, cgraph->vwgt,
cgraph->adjwgt, &wgtflag, &numflag, &nparts, tpwgts, options,
&edgecut, cgraph->where);
IFSET(ctrl->dbglvl, DBG_TIME, stoptimer(ctrl->InitPartTmr));
IFSET(ctrl->dbglvl, DBG_IPART, printf("Initial %d-way partitioning cut: %d\n", nparts, edgecut));
IFSET(ctrl->dbglvl, DBG_KWAYPINFO, ComputePartitionInfo(cgraph, nparts, cgraph->where));
RefineVolKWay(ctrl, graph, cgraph, nparts, tpwgts, ubfactor);
idxcopy(graph->nvtxs, graph->where, part);
GKfree((void **)&graph->gdata, &graph->rdata, LTERM);
return graph->minvol;
}
/*************************************************************************
* This function projects a partition, and at the same time computes the
* parameters for refinement.
**************************************************************************/
void ProjectVolKWayPartition(CtrlType *ctrl, GraphType *graph, int nparts)
{
int i, j, k, nvtxs, me, other, istart, iend, ndegrees;
idxtype *xadj, *adjncy, *adjwgt, *adjwgtsum;
idxtype *cmap, *where;
idxtype *cwhere;
GraphType *cgraph;
VRInfoType *crinfo, *rinfo, *myrinfo;
VEDegreeType *myedegrees;
idxtype *htable;
cgraph = graph->coarser;
cwhere = cgraph->where;
crinfo = cgraph->vrinfo;
nvtxs = graph->nvtxs;
cmap = graph->cmap;
xadj = graph->xadj;
adjncy = graph->adjncy;
adjwgt = graph->adjwgt;
adjwgtsum = graph->adjwgtsum;
AllocateVolKWayPartitionMemory(ctrl, graph, nparts);
where = graph->where;
rinfo = graph->vrinfo;
/* Go through and project partition and compute id/ed for the nodes */
for (i=0; i<nvtxs; i++) {
k = cmap[i];
where[i] = cwhere[k];
cmap[i] = crinfo[k].ed; /* For optimization */
}
htable = idxset(nparts, -1, idxwspacemalloc(ctrl, nparts));
ctrl->wspace.cdegree = 0;
for (i=0; i<nvtxs; i++) {
me = where[i];
myrinfo = rinfo+i;
myrinfo->id = myrinfo->ed = myrinfo->nid = myrinfo->ndegrees = 0;
myrinfo->edegrees = NULL;
myrinfo->id = adjwgtsum[i];
myrinfo->nid = xadj[i+1]-xadj[i];
if (cmap[i] > 0) { /* If it is an interface node. Note cmap[i] = crinfo[cmap[i]].ed */
istart = xadj[i];
iend = xadj[i+1];
myedegrees = myrinfo->edegrees = ctrl->wspace.vedegrees+ctrl->wspace.cdegree;
ctrl->wspace.cdegree += iend-istart;
ndegrees = 0;
for (j=istart; j<iend; j++) {
other = where[adjncy[j]];
if (me != other) {
myrinfo->ed += adjwgt[j];
myrinfo->nid--;
if ((k = htable[other]) == -1) {
htable[other] = ndegrees;
myedegrees[ndegrees].gv = 0;
myedegrees[ndegrees].pid = other;
myedegrees[ndegrees].ed = adjwgt[j];
myedegrees[ndegrees++].ned = 1;
}
else {
myedegrees[k].ed += adjwgt[j];
myedegrees[k].ned++;
}
}
}
myrinfo->id -= myrinfo->ed;
/* Remove space for edegrees if it was interior */
if (myrinfo->ed == 0) {
myrinfo->edegrees = NULL;
ctrl->wspace.cdegree -= iend-istart;
}
else {
myrinfo->ndegrees = ndegrees;
for (j=0; j<ndegrees; j++)
htable[myedegrees[j].pid] = -1;
}
}
}
ComputeKWayVolGains(ctrl, graph, nparts);
idxcopy(nparts, cgraph->pwgts, graph->pwgts);
graph->mincut = cgraph->mincut;
FreeGraph(graph->coarser);
graph->coarser = NULL;
idxwspacefree(ctrl, nparts);
}
