xref: /petsc/src/mat/impls/aij/seq/crl/ftn-kernels/fmultcrl.F90 (revision fe66ebcc023cb303106674d426ee542bea707d38)
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3c96caaccSSatish Balay!    Fortran kernel for sparse matrix-vector product in the AIJ/CRL format
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5c96caaccSSatish Balay#include <petsc/finclude/petscsys.h>
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70ccf82acSMartin Diehlpure subroutine FortranMultCRL(m,rmax,x,y,icols,acols)
8*fe66ebccSMartin Diehl  use, intrinsic :: ISO_C_binding
90ccf82acSMartin Diehl  implicit none (type, external)
100ccf82acSMartin Diehl  PetscInt, intent(in) :: m,rmax,icols(m,rmax)
110ccf82acSMartin Diehl  PetscScalar, intent(in) :: x(0:m-1), acols(m,rmax)
120ccf82acSMartin Diehl  PetscScalar, intent(out) :: y(m)
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14d66e387eSMartin Diehl  PetscInt :: i
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16d66e387eSMartin Diehl  y(1:m) = acols(1:m,1)*x(icols(1:m,1))
170113e719SMartin Diehl  do i=2,rmax
18d66e387eSMartin Diehl    y(1:m) = y(1:m) + acols(1:m,i)*x(icols(1:m,i))
190113e719SMartin Diehl  end do
200113e719SMartin Diehlend subroutine FortranMultCRL
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