petsc-3.8.4 2018-03-24

DMDAGetRay

Returns a vector on process zero that contains a row or column of the values in a DMDA vector

#include "petscdmda.h"   
PetscErrorCode  DMDAGetRay(DM da,DMDADirection dir,PetscInt gp,Vec *newvec,VecScatter *scatter)

Collective on DMDA

	da	- the distributed array
	vec	- the vector
	dir	- Cartesian direction, either DMDA_X, DMDA_Y, or DMDA_Z
	gp	- global grid point number in this direction

	newvec	- the new vector that can hold the values (size zero on all processes except process 0)
	scatter	- the VecScatter that will map from the original vector to the slice

All processors that share the DMDA must call this with the same gp value

distributed array, get, processor subset