petsc-3.3-p7 2013-05-11

VecScatterCreateToZero

 Creates an output vector and a scatter context used to copy all vector values into the output vector on the zeroth processor

Synopsis

#include "petscvec.h" 
PetscErrorCode  VecScatterCreateToZero(Vec vin,VecScatter *ctx,Vec *vout)
Collective on Vec

Input Parameter

vin -input MPIVEC

Output Parameter

ctx - scatter context
vout - output SEQVEC that is large enough to scatter into on processor 0 and of length zero on all other processors

Note: vout may be PETSC_NULL [PETSC_NULL_OBJECT from fortran] if you do not need to have it created

Usage

       VecScatterCreateToZero(vin,&ctx,&vout);



       // scatter as many times as you need



       VecScatterBegin(ctx,vin,vout,INSERT_VALUES,SCATTER_FORWARD);



       VecScatterEnd(ctx,vin,vout,INSERT_VALUES,SCATTER_FORWARD);





       // destroy scatter context and local vector when no longer needed



       VecScatterDestroy(ctx);



       VecDestroy(vout);





See Also

VecScatterCreate(), VecScatterCreateToAll(), VecScatterBegin(), VecScatterEnd()




Do NOT create a vector and then pass it in as the final argument vout! vout is created by this routine
automatically (unless you pass PETSC_NULL in for that argument if you do not need it).



Level:intermediate

Location:src/vec/vec/utils/vecmpitoseq.c

Index of all Vec routines

Table of Contents for all manual pages

Index of all manual pages