VecAXPY#

Computes y = alpha x + y.

Synopsis#

#include "petscvec.h"   
PetscErrorCode VecAXPY(Vec y, PetscScalar alpha, Vec x)

Logically Collective

Input Parameters#

  • alpha - the scalar

  • x - vector scale by alpha

  • y - vector accumulated into

Output Parameter#

  • y - output vector

Notes#

This routine is optimized for alpha of 0.0, otherwise it calls the BLAS routine

    VecAXPY(y,alpha,x)                   y = alpha x           +      y
    VecAYPX(y,beta,x)                    y =       x           + beta y
    VecAXPBY(y,alpha,beta,x)             y = alpha x           + beta y
    VecWAXPY(w,alpha,x,y)                w = alpha x           +      y
    VecAXPBYPCZ(z,alpha,beta,gamma,x,y)  z = alpha x           + beta y + gamma z
    VecMAXPY(y,nv,alpha[],x[])           y = sum alpha[i] x[i] +      y

See Also#

Vectors and Parallel Data, Vec, VecAYPX(), VecMAXPY(), VecWAXPY(), VecAXPBYPCZ(), VecAXPBY()

Level#

intermediate

Location#

src/vec/vec/interface/rvector.c

Examples#

src/tao/unconstrained/tutorials/eptorsion1.c
src/tao/constrained/tutorials/maros.c
src/tao/constrained/tutorials/ex1.c
src/tao/leastsquares/tutorials/tomography.c
src/tao/unconstrained/tutorials/rosenbrock1.c
src/tao/unconstrained/tutorials/eptorsion3.c
src/tao/tutorials/ex4.c
src/tao/constrained/tutorials/tomographyADMM.c
src/tao/tutorials/ex3.c
src/tao/bound/tutorials/jbearing2.c

Implementations#

VecAXPY_Nest() in src/vec/vec/impls/nest/vecnest.c
VecAXPY_Seq() in src/vec/vec/impls/seq/bvec1.c
VecAXPY_SeqKokkos() in src/vec/vec/impls/seq/kokkos/veckok.kokkos.cxx
VecAXPY_SeqViennaCL() in src/vec/vec/impls/seq/seqviennacl/vecviennacl.cxx


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Index of all manual pages