 /* 
  * mcoarsen.c 
  * 
  * This file contains the driving routines for the coarsening process  
  * 
  * Started 7/23/97 
  * George 
  * 
  * $Id: mcoarsen.c,v 1.1 1998/11/27 17:59:19 karypis Exp $ 
  * 
  */ 

 #include <metis.h> 


 /************************************************************************* 
 * This function takes a graph and creates a sequence of coarser graphs 
 **************************************************************************/ 
 GraphType *MCCoarsen2Way(CtrlType *ctrl, GraphType *graph) 
 { 
   long i, clevel; 
   GraphType *cgraph; 

   IFSET(ctrl->dbglvl, DBG_TIME, starttimer(ctrl->CoarsenTmr)); 

   cgraph = graph; 

   clevel = 0; 
   do { 
     if (ctrl->dbglvl&DBG_COARSEN) { 
       printf("%6ld %7ld %10ld [%ld] [%6.4f", cgraph->nvtxs, cgraph->nedges,  
               idxsum(cgraph->nvtxs, cgraph->adjwgtsum), ctrl->CoarsenTo, ctrl->nmaxvwgt); 
       for (i=0; i<graph->ncon; i++) 
         printf(" %5.3f", ssum_strd(cgraph->nvtxs, cgraph->nvwgt+i, cgraph->ncon)); 
       printf("]\n"); 
     } 

     switch (ctrl->CType) { 
       case MATCH_RM: 
         MCMatch_RM(ctrl, cgraph); 
         break; 
       case MATCH_HEM: 
         if (clevel < 1) 
           MCMatch_RM(ctrl, cgraph); 
         else 
           MCMatch_HEM(ctrl, cgraph); 
         break; 
       case MATCH_SHEM: 
         if (clevel < 1) 
           MCMatch_RM(ctrl, cgraph); 
         else 
           MCMatch_SHEM(ctrl, cgraph); 
         break; 
       case MATCH_SHEMKWAY: 
         MCMatch_SHEM(ctrl, cgraph); 
         break; 
       case MATCH_SHEBM_ONENORM: 
         MCMatch_SHEBM(ctrl, cgraph, 1); 
         break; 
       case MATCH_SHEBM_INFNORM: 
         MCMatch_SHEBM(ctrl, cgraph, -1); 
         break; 
       case MATCH_SBHEM_ONENORM: 
         MCMatch_SBHEM(ctrl, cgraph, 1); 
         break; 
       case MATCH_SBHEM_INFNORM: 
         MCMatch_SBHEM(ctrl, cgraph, -1); 
         break; 
       default: 
         errexit("Unknown CType: %ld\n", ctrl->CType); 
     } 

     cgraph = cgraph->coarser; 
     clevel++; 

   } while (cgraph->nvtxs > ctrl->CoarsenTo && cgraph->nvtxs < COARSEN_FRACTION2*cgraph->finer->nvtxs && cgraph->nedges > cgraph->nvtxs/2);  

   if (ctrl->dbglvl&DBG_COARSEN) { 
     printf("%6ld %7ld %10ld [%ld] [%6.4f", cgraph->nvtxs, cgraph->nedges,  
             idxsum(cgraph->nvtxs, cgraph->adjwgtsum), ctrl->CoarsenTo, ctrl->nmaxvwgt); 
     for (i=0; i<graph->ncon; i++) 
       printf(" %5.3f", ssum_strd(cgraph->nvtxs, cgraph->nvwgt+i, cgraph->ncon)); 
     printf("]\n"); 
   } 


   IFSET(ctrl->dbglvl, DBG_TIME, stoptimer(ctrl->CoarsenTmr)); 

   return cgraph; 
 } 

