Actual source code: smg.c

  1: /*$Id: smg.c,v 1.24 2001/08/07 03:03:36 balay Exp $*/
  2: /*
  3:      Additive Multigrid V Cycle routine    
  4: */
 5:  #include src/ksp/pc/impls/mg/mgimpl.h

  7: /*
  8:        MGACycle_Private - Given an MG structure created with MGCreate() runs 
  9:                   one cycle down through the levels and back up. Applys
 10:                   the smoothers in an additive manner.

 12:     Iput Parameters:
 13: .   mg - structure created with  MGCreate().

 15: */
 18: int MGACycle_Private(MG *mg)
 19: {
 20:   int    i,l = mg[0]->levels,ierr;
 21:   PetscScalar zero = 0.0;

 24:   /* compute RHS on each level */
 25:   for (i=l-1; i>0; i--) {
 26:     MatRestrict(mg[i]->restrct,mg[i]->b,mg[i-1]->b);
 27:   }
 28:   /* solve seperately on each level */
 29:   for (i=0; i<l; i++) {
 30:     VecSet(&zero,mg[i]->x);
 31:     if (mg[i]->eventsolve) {PetscLogEventBegin(mg[i]->eventsolve,0,0,0,0);}
 32:     KSPSetRhs(mg[i]->smoothd,mg[i]->b);
 33:     KSPSetSolution(mg[i]->smoothd,mg[i]->x);
 34:     KSPSolve(mg[i]->smoothd);
 35:     if (mg[i]->eventsolve) {PetscLogEventEnd(mg[i]->eventsolve,0,0,0,0);}
 36:   }
 37:   for (i=1; i<l; i++) {
 38:     MatInterpolateAdd(mg[i]->interpolate,mg[i-1]->x,mg[i]->x,mg[i]->x);
 39:   }
 40:   return(0);
 41: }