VecDot#

Computes the vector dot product.

Synopsis#

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

Collective

Input Parameters#

  • x - first vector

  • y - second vector

Output Parameter#

  • val - the dot product

Notes for Users of Complex Numbers#

For complex vectors, VecDot() computes

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

where y^H denotes the conjugate transpose of y. Note that this corresponds to the usual “mathematicians” complex inner product where the SECOND argument gets the complex conjugate. Since the BLASdot() complex conjugates the first first argument we call the BLASdot() with the arguments reversed.

Use VecTDot() for the indefinite form

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

where y^T denotes the transpose of y.

See Also#

Vectors and Parallel Data, Vec, VecMDot(), VecTDot(), VecNorm(), VecDotBegin(), VecDotEnd(), VecDotRealPart()

Level#

intermediate

Location#

src/vec/vec/interface/rvector.c

Examples#

src/tao/unconstrained/tutorials/spectraladjointassimilation.c
src/tao/bound/tutorials/jbearing2.c
src/tao/pde_constrained/tutorials/elliptic.c
src/tao/constrained/tutorials/maros.c
src/tao/pde_constrained/tutorials/parabolic.c
src/tao/tutorials/ex4.c
src/tao/leastsquares/tutorials/tomography.c
src/tao/unconstrained/tutorials/burgers_spectral.c
src/tao/tutorials/ex3.c
src/tao/constrained/tutorials/tomographyADMM.c

Implementations#

VecDot_MPIKokkos() in src/vec/vec/impls/mpi/kokkos/mpikok.kokkos.cxx
VecDot_MPIViennaCL() in src/vec/vec/impls/mpi/mpiviennacl/mpiviennacl.cxx
VecDot_MPI() in src/vec/vec/impls/mpi/pvec2.c
VecDot_Nest() in src/vec/vec/impls/nest/vecnest.c
VecDot_Seq() in src/vec/vec/impls/seq/bvec1.c
VecDot_SeqKokkos() in src/vec/vec/impls/seq/kokkos/veckok.kokkos.cxx
VecDot_SeqViennaCL() in src/vec/vec/impls/seq/seqviennacl/vecviennacl.cxx


Index of all Vec routines
Table of Contents for all manual pages
Index of all manual pages