VecSetValues#
Inserts or adds values into certain locations of a vector.
Synopsis#
#include "petscvec.h"
PetscErrorCode VecSetValues(Vec x, PetscInt ni, const PetscInt ix[], const PetscScalar y[], InsertMode iora)
Not Collective
Input Parameters#
x - vector to insert in
ni - number of elements to add
ix - indices where to add
y - array of values
iora - either
INSERT_VALUESto replace the current values orADD_VALUESto add values to any existing entries
Notes#
`VecSetValues()` sets x[ix[i]] = y[i], for i=0,...,ni-1.
Calls to VecSetValues() with the INSERT_VALUES and ADD_VALUES
options cannot be mixed without intervening calls to the assembly
routines.
These values may be cached, so VecAssemblyBegin() and VecAssemblyEnd()
MUST be called after all calls to VecSetValues() have been completed.
VecSetValues() uses 0-based indices in Fortran as well as in C.
If you call VecSetOption(x, VEC_IGNORE_NEGATIVE_INDICES,PETSC_TRUE),
negative indices may be passed in ix. These rows are
simply ignored. This allows easily inserting element load matrices
with homogeneous Dirichlet boundary conditions that you don’t want represented
in the vector.
Fortran Note#
If any of ix and y are scalars pass them using, for example,
VecSetValues(mat, one, [ix], [y], INSERT_VALUES)
See Also#
Vectors and Parallel Data, Vec, VecAssemblyBegin(), VecAssemblyEnd(), VecSetValuesLocal(),
VecSetValue(), VecSetValuesBlocked(), InsertMode, INSERT_VALUES, ADD_VALUES, VecGetValues()
Level#
beginner
Location#
Examples#
src/vec/vec/tutorials/ex5.c
src/vec/vec/tutorials/ex2f.F90
src/vec/vec/tutorials/ex14f.F90
src/vec/vec/tutorials/ex9f.F90
src/vec/vec/tutorials/ex5f.F90
src/vec/vec/tutorials/ex44.c
src/vec/vec/tutorials/ex2.c
src/vec/vec/tutorials/ex3f.F90
src/vec/vec/tutorials/ex18.c
src/vec/vec/tutorials/ex4f90.F90
Implementations#
VecSetValues_MPI() in src/vec/vec/impls/mpi/pdvec.c
VecSetValues_Seq() in src/vec/vec/impls/seq/bvec2.c
Index of all Vec routines
Table of Contents for all manual pages
Index of all manual pages