/*@C
KSPGetOperatorsSet - Determines if the matrix associated with the linear system and
possibly a different one associated with the preconditioner have been set in the KSP.
Not collective, though the results on all processes should be the same
Input Parameter:
. pc - the KSP context
Output Parameters:
+ mat - the matrix associated with the linear system was set
- pmat - matrix associated with the preconditioner was set, usually the same
Level: intermediate
.keywords: KSP, get, operators, matrix, linear system
.seealso: PCSetOperators(), KSPGetOperators(), KSPSetOperators(), PCGetOperators(), PCGetOperatorsSet()
@*/
PetscErrorCode KSPGetOperatorsSet(KSP ksp,PetscBool *mat,PetscBool *pmat)
{
PetscErrorCode ierr;
PetscFunctionBegin;
PetscValidHeaderSpecific(ksp,KSP_CLASSID,1);
if (!ksp->pc) {ierr = KSPGetPC(ksp,&ksp->pc);CHKERRQ(ierr);}
ierr = PCGetOperatorsSet(ksp->pc,mat,pmat);CHKERRQ(ierr);
PetscFunctionReturn(0);
}
/*@C
KSPCreateVecs - Gets a number of work vectors.
Input Parameters:
+ ksp - iterative context
. rightn - number of right work vectors
- leftn - number of left work vectors to allocate
Output Parameter:
+ right - the array of vectors created
- left - the array of left vectors
Note: The right vector has as many elements as the matrix has columns. The left
vector has as many elements as the matrix has rows.
The vectors are new vectors that are not owned by the KSP, they should be destroyed with calls to VecDestroyVecs() when no longer needed.
Developers Note: First tries to duplicate the rhs and solution vectors of the KSP, if they do not exist tries to get them from the matrix, if
that does not exist tries to get them from the DM (if it is provided).
Level: advanced
.seealso: MatCreateVecs(), VecDestroyVecs()
@*/
PetscErrorCode KSPCreateVecs(KSP ksp,PetscInt rightn, Vec **right,PetscInt leftn,Vec **left)
{
PetscErrorCode ierr;
Vec vecr = NULL,vecl = NULL;
PetscBool matset,pmatset;
Mat mat = NULL;
PetscFunctionBegin;
if (rightn) {
if (!right) SETERRQ(PetscObjectComm((PetscObject)ksp),PETSC_ERR_ARG_INCOMP,"You asked for right vectors but did not pass a pointer to hold them");
if (ksp->vec_sol) vecr = ksp->vec_sol;
else {
if (ksp->pc) {
ierr = PCGetOperatorsSet(ksp->pc,&matset,&pmatset);CHKERRQ(ierr);
/* check for mat before pmat because for KSPLSQR pmat may be a different size than mat since pmat maybe mat'*mat */
if (matset) {
ierr = PCGetOperators(ksp->pc,&mat,NULL);CHKERRQ(ierr);
ierr = MatCreateVecs(mat,&vecr,NULL);CHKERRQ(ierr);
} else if (pmatset) {
ierr = PCGetOperators(ksp->pc,NULL,&mat);CHKERRQ(ierr);
ierr = MatCreateVecs(mat,&vecr,NULL);CHKERRQ(ierr);
}
}
if (!vecr) {
if (ksp->dm) {
ierr = DMGetGlobalVector(ksp->dm,&vecr);CHKERRQ(ierr);
} else SETERRQ(PetscObjectComm((PetscObject)ksp),PETSC_ERR_ARG_WRONGSTATE,"You requested a vector from a KSP that cannot provide one");
}
}
ierr = VecDuplicateVecs(vecr,rightn,right);CHKERRQ(ierr);
if (!ksp->vec_sol) {
if (mat) {
ierr = VecDestroy(&vecr);CHKERRQ(ierr);
} else if (ksp->dm) {
ierr = DMRestoreGlobalVector(ksp->dm,&vecr);CHKERRQ(ierr);
}
}
}
if (leftn) {
if (!left) SETERRQ(PetscObjectComm((PetscObject)ksp),PETSC_ERR_ARG_INCOMP,"You asked for left vectors but did not pass a pointer to hold them");
if (ksp->vec_rhs) vecl = ksp->vec_rhs;
else {
if (ksp->pc) {
ierr = PCGetOperatorsSet(ksp->pc,&matset,&pmatset);CHKERRQ(ierr);
/* check for mat before pmat because for KSPLSQR pmat may be a different size than mat since pmat maybe mat'*mat */
if (matset) {
ierr = PCGetOperators(ksp->pc,&mat,NULL);CHKERRQ(ierr);
ierr = MatCreateVecs(mat,NULL,&vecl);CHKERRQ(ierr);
} else if (pmatset) {
ierr = PCGetOperators(ksp->pc,NULL,&mat);CHKERRQ(ierr);
ierr = MatCreateVecs(mat,NULL,&vecl);CHKERRQ(ierr);
}
}
if (!vecl) {
if (ksp->dm) {
ierr = DMGetGlobalVector(ksp->dm,&vecl);CHKERRQ(ierr);
} else SETERRQ(PetscObjectComm((PetscObject)ksp),PETSC_ERR_ARG_WRONGSTATE,"You requested a vector from a KSP that cannot provide one");
}
}
ierr = VecDuplicateVecs(vecl,leftn,left);CHKERRQ(ierr);
if (!ksp->vec_rhs) {
if (mat) {
ierr = VecDestroy(&vecl);CHKERRQ(ierr);
} else if (ksp->dm) {
ierr = DMRestoreGlobalVector(ksp->dm,&vecl);CHKERRQ(ierr);
}
}
}
PetscFunctionReturn(0);
}
