xref: /petsc/src/ksp/pc/impls/none/none.c (revision 95452b02e12c0ee11232c7ff2b24b568a8e07e43)
1dba47a55SKris Buschelman 
24b9ad928SBarry Smith /*
34b9ad928SBarry Smith     Identity preconditioner, simply copies vector x to y.
44b9ad928SBarry Smith */
5af0996ceSBarry Smith #include <petsc/private/pcimpl.h>          /*I "petscpc.h" I*/
64b9ad928SBarry Smith 
7dfbe8321SBarry Smith PetscErrorCode PCApply_None(PC pc,Vec x,Vec y)
84b9ad928SBarry Smith {
9dfbe8321SBarry Smith   PetscErrorCode ierr;
104b9ad928SBarry Smith 
114b9ad928SBarry Smith   PetscFunctionBegin;
124b9ad928SBarry Smith   ierr = VecCopy(x,y);CHKERRQ(ierr);
134b9ad928SBarry Smith   PetscFunctionReturn(0);
144b9ad928SBarry Smith }
154b9ad928SBarry Smith 
164b9ad928SBarry Smith /*MC
174b9ad928SBarry Smith      PCNONE - This is used when you wish to employ a nonpreconditioned
184b9ad928SBarry Smith              Krylov method.
194b9ad928SBarry Smith 
204b9ad928SBarry Smith    Level: beginner
214b9ad928SBarry Smith 
224b9ad928SBarry Smith   Concepts: preconditioners
234b9ad928SBarry Smith 
24*95452b02SPatrick Sanan   Notes:
25*95452b02SPatrick Sanan     This is implemented by a VecCopy()
264b9ad928SBarry Smith 
274b9ad928SBarry Smith .seealso:  PCCreate(), PCSetType(), PCType (for list of available types), PC
284b9ad928SBarry Smith M*/
294b9ad928SBarry Smith 
308cc058d9SJed Brown PETSC_EXTERN PetscErrorCode PCCreate_None(PC pc)
314b9ad928SBarry Smith {
324b9ad928SBarry Smith   PetscFunctionBegin;
334b9ad928SBarry Smith   pc->ops->apply               = PCApply_None;
344b9ad928SBarry Smith   pc->ops->applytranspose      = PCApply_None;
354b9ad928SBarry Smith   pc->ops->destroy             = 0;
364b9ad928SBarry Smith   pc->ops->setup               = 0;
374b9ad928SBarry Smith   pc->ops->view                = 0;
384b9ad928SBarry Smith   pc->ops->applysymmetricleft  = PCApply_None;
394b9ad928SBarry Smith   pc->ops->applysymmetricright = PCApply_None;
404b9ad928SBarry Smith 
414b9ad928SBarry Smith   pc->data = 0;
424b9ad928SBarry Smith   PetscFunctionReturn(0);
434b9ad928SBarry Smith }
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