petsc-3.4.2 2013-07-02

# VecNormBegin

Starts a split phase norm computation.

### Synopsis

    #include "petscvec.h"
    PetscErrorCode  VecNormBegin(Vec x,NormType ntype,PetscReal *result)

### Input Parameters

| x | - the first vector
| ntype | - norm type, one of NORM_1, NORM_2, NORM_MAX, NORM_1_AND_2
| result | - where the result will go (can be NULL)

### Notes

Each call to VecNormBegin() should be paired with a call to VecNormEnd().

### See Also

VecNormEnd(), VecNorm(), VecDot(), VecMDot(), VecDotBegin(), VecDotEnd(), PetscCommSplitReductionBegin()

Level:advanced
Location: src/vec/vec/utils/comb.c
Index of all Vec routines
Table of Contents for all manual pages
Index of all manual pages