xref: /petsc/src/mat/impls/shell/shellcnv.c (revision b0a32e0c6855ee6a6cd3495fa7da12ea9885bc5d)
1*b0a32e0cSBarry Smith /*$Id: shellcnv.c,v 1.16 2000/10/24 20:25:38 bsmith Exp bsmith $*/
26098dc10SBarry Smith 
3e090d566SSatish Balay #include "src/mat/matimpl.h"        /*I "petscmat.h" I*/
46098dc10SBarry Smith #include "src/vec/vecimpl.h"
56098dc10SBarry Smith 
66098dc10SBarry Smith #undef __FUNC__
7*b0a32e0cSBarry Smith #define __FUNC__ "MatConvert_Shell"
86098dc10SBarry Smith int MatConvert_Shell(Mat oldmat,MatType newtype,Mat *mat)
96098dc10SBarry Smith {
106098dc10SBarry Smith   Vec      in,out;
11273d9f13SBarry Smith   int      ierr,i,M,m,*rows,start,end;
126098dc10SBarry Smith   MPI_Comm comm;
136098dc10SBarry Smith   Scalar   *array,zero = 0.0,one = 1.0;
146098dc10SBarry Smith 
153a40ed3dSBarry Smith   PetscFunctionBegin;
166098dc10SBarry Smith   PetscValidHeaderSpecific(oldmat,MAT_COOKIE);
176098dc10SBarry Smith   PetscValidPointer(mat);
186098dc10SBarry Smith   comm = oldmat->comm;
196098dc10SBarry Smith 
206098dc10SBarry Smith   ierr = MatGetOwnershipRange(oldmat,&start,&end);CHKERRQ(ierr);
216098dc10SBarry Smith   ierr = VecCreateMPI(comm,end-start,PETSC_DECIDE,&in);CHKERRQ(ierr);
226098dc10SBarry Smith   ierr = VecDuplicate(in,&out);CHKERRQ(ierr);
236098dc10SBarry Smith   ierr = VecGetSize(in,&M);CHKERRQ(ierr);
246098dc10SBarry Smith   ierr = VecGetLocalSize(in,&m);CHKERRQ(ierr);
25*b0a32e0cSBarry Smith   ierr = PetscMalloc((m+1)*sizeof(int),&rows);CHKERRQ(ierr);
266098dc10SBarry Smith   for (i=0; i<m; i++) {rows[i] = start + i;}
276098dc10SBarry Smith 
28273d9f13SBarry Smith   ierr = MatCreate(comm,m,M,M,M,mat);CHKERRQ(ierr);
29273d9f13SBarry Smith   ierr = MatSetType(*mat,newtype);CHKERRQ(ierr);
306098dc10SBarry Smith 
316098dc10SBarry Smith   for (i=0; i<M; i++) {
326098dc10SBarry Smith     ierr = VecSet(&zero,in);CHKERRQ(ierr);
336098dc10SBarry Smith     ierr = VecSetValues(in,1,&i,&one,INSERT_VALUES);CHKERRQ(ierr);
346098dc10SBarry Smith     ierr = VecAssemblyBegin(in);CHKERRQ(ierr);
356098dc10SBarry Smith     ierr = VecAssemblyEnd(in);CHKERRQ(ierr);
366098dc10SBarry Smith 
376098dc10SBarry Smith     ierr = MatMult(oldmat,in,out);CHKERRQ(ierr);
386098dc10SBarry Smith 
396098dc10SBarry Smith     ierr = VecGetArray(out,&array);CHKERRQ(ierr);
406098dc10SBarry Smith     ierr = MatSetValues(*mat,m,rows,1,&i,array,INSERT_VALUES);CHKERRQ(ierr);
416098dc10SBarry Smith     ierr = VecRestoreArray(out,&array);CHKERRQ(ierr);
426098dc10SBarry Smith 
436098dc10SBarry Smith   }
44606d414cSSatish Balay   ierr = PetscFree(rows);CHKERRQ(ierr);
456098dc10SBarry Smith   ierr = VecDestroy(in);CHKERRQ(ierr);
466098dc10SBarry Smith   ierr = VecDestroy(out);CHKERRQ(ierr);
476098dc10SBarry Smith   ierr = MatAssemblyBegin(*mat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
486098dc10SBarry Smith   ierr = MatAssemblyEnd(*mat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
493a40ed3dSBarry Smith   PetscFunctionReturn(0);
506098dc10SBarry Smith }
516098dc10SBarry Smith 
526098dc10SBarry Smith 
536098dc10SBarry Smith 
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