petsc-3.4.5 2014-06-29

PetscThreadReductionBegin

Initiates a threaded reduction and returns a reduction object to be passed to PetscThreadCommRunKernel

Synopsis

#include "petscthreadcomm.h" 
PetscErrorCode PetscThreadReductionBegin(MPI_Comm comm,PetscThreadCommReductionOp op, PetscDataType type,PetscInt nreds,PetscThreadCommReduction *redout)

Input Parameters

	comm	- the MPI comm
	op	- the reduction operation
	type	- the data type for reduction
	nreds	- Number of reductions

Output Parameters

redout -the reduction context

Notes

See include/petscthreadcomm.h for the available reduction operations

To be called from the main thread before calling PetscThreadCommRunKernel

Examples