VecDot

Computes the vector dot product.

#include "petscvec.h" 
PetscErrorCode  VecDot(Vec x,Vec y,PetscScalar *val)

Collective on Vec

x, y -the vectors

val -the dot product

For complex vectors, VecDot() computes

    val = (x,y) = y^H x,

where y^H denotes the conjugate transpose of y.

Use VecTDot() for the indefinite form

    val = (x,y) = y^T x,

where y^T denotes the transpose of y.

	per	- processor memory bandwidth
	interprocessor latency	- - work load inbalance that causes certain processes to arrive much earlier than others

PetscScalar VecDot(Vec x,Vec y)

VecDot(x,y,&s); return s;