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

124 lines
3.7 KiB
C

/*
* Copyright 1997, Regents of the University of Minnesota
*
* mkmetis.c
*
* This file contains the top level routines for the multilevel k-way partitioning
* algorithm KMETIS.
*
* Started 7/28/97
* George
*
* $Id: mkmetis.c,v 1.3 2002/08/10 07:07:27 karypis Exp $
*
*/
#include <metislib.h>
/*************************************************************************
* This function is the entry point for KWMETIS
**************************************************************************/
void METIS_mCPartGraphKway(idxtype *nvtxs, idxtype *ncon, idxtype *xadj, idxtype *adjncy,
idxtype *vwgt, idxtype *adjwgt, idxtype *wgtflag, idxtype *numflag,
idxtype *nparts, float *rubvec, idxtype *options, idxtype *edgecut,
idxtype *part)
{
idxtype i, j;
GraphType graph;
CtrlType ctrl;
if (*numflag == 1)
Change2CNumbering(*nvtxs, xadj, adjncy);
SetUpGraph(&graph, OP_KMETIS, *nvtxs, *ncon, xadj, adjncy, vwgt, adjwgt, *wgtflag);
if (options[0] == 0) { /* Use the default parameters */
ctrl.CType = McKMETIS_CTYPE;
ctrl.IType = McKMETIS_ITYPE;
ctrl.RType = McKMETIS_RTYPE;
ctrl.dbglvl = McKMETIS_DBGLVL;
}
else {
ctrl.CType = options[OPTION_CTYPE];
ctrl.IType = options[OPTION_ITYPE];
ctrl.RType = options[OPTION_RTYPE];
ctrl.dbglvl = options[OPTION_DBGLVL];
}
ctrl.optype = OP_KMETIS;
ctrl.CoarsenTo = amax((*nvtxs)/(20*gk_log2(*nparts)), 30*(*nparts));
ctrl.nmaxvwgt = 1.5/(1.0*ctrl.CoarsenTo);
InitRandom(-1);
AllocateWorkSpace(&ctrl, &graph, *nparts);
IFSET(ctrl.dbglvl, DBG_TIME, InitTimers(&ctrl));
IFSET(ctrl.dbglvl, DBG_TIME, gk_startcputimer(ctrl.TotalTmr));
*edgecut = MCMlevelKWayPartitioning(&ctrl, &graph, *nparts, part, rubvec);
IFSET(ctrl.dbglvl, DBG_TIME, gk_stopcputimer(ctrl.TotalTmr));
IFSET(ctrl.dbglvl, DBG_TIME, PrintTimers(&ctrl));
FreeWorkSpace(&ctrl, &graph);
if (*numflag == 1)
Change2FNumbering(*nvtxs, xadj, adjncy, part);
}
/*************************************************************************
* This function takes a graph and produces a bisection of it
**************************************************************************/
idxtype MCMlevelKWayPartitioning(CtrlType *ctrl, GraphType *graph, idxtype nparts, idxtype *part,
float *rubvec)
{
idxtype i, j, nvtxs;
GraphType *cgraph;
idxtype options[10], edgecut;
cgraph = MCCoarsen2Way(ctrl, graph);
IFSET(ctrl->dbglvl, DBG_TIME, gk_startcputimer(ctrl->InitPartTmr));
MocAllocateKWayPartitionMemory(ctrl, cgraph, nparts);
options[0] = 1;
options[OPTION_CTYPE] = MTYPE_SBHEM_INFNORM;
options[OPTION_ITYPE] = ITYPE_RANDOM;
options[OPTION_RTYPE] = RTYPE_FM;
options[OPTION_DBGLVL] = 0;
/* Determine what you will use as the initial partitioner, based on tolerances */
for (i=0; i<graph->ncon; i++) {
if (rubvec[i] > 1.2)
break;
}
if (i == graph->ncon)
METIS_mCPartGraphRecursiveInternal(&cgraph->nvtxs, &cgraph->ncon,
cgraph->xadj, cgraph->adjncy, cgraph->nvwgt, cgraph->adjwgt, &nparts,
options, &edgecut, cgraph->where);
else
METIS_mCHPartGraphRecursiveInternal(&cgraph->nvtxs, &cgraph->ncon,
cgraph->xadj, cgraph->adjncy, cgraph->nvwgt, cgraph->adjwgt, &nparts,
rubvec, options, &edgecut, cgraph->where);
IFSET(ctrl->dbglvl, DBG_TIME, gk_stopcputimer(ctrl->InitPartTmr));
IFSET(ctrl->dbglvl, DBG_IPART, mprintf("Initial %D-way partitioning cut: %D\n", nparts, edgecut));
IFSET(ctrl->dbglvl, DBG_KWAYPINFO, ComputePartitionInfo(cgraph, nparts, cgraph->where));
MocRefineKWayHorizontal(ctrl, graph, cgraph, nparts, rubvec);
idxcopy(graph->nvtxs, graph->where, part);
FreeGraph(graph, 0);
return graph->mincut;
}