xref: /petsc/src/mat/impls/aij/seq/crl/ftn-kernels/fmultcrl.F90 (revision 0ccf82ac36648ce52b79cfc8b55f689a1594b19a)
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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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7*0ccf82acSMartin Diehlpure subroutine FortranMultCRL(m,rmax,x,y,icols,acols)
8*0ccf82acSMartin Diehl  implicit none (type, external)
9*0ccf82acSMartin Diehl  PetscInt, intent(in) :: m,rmax,icols(m,rmax)
10*0ccf82acSMartin Diehl  PetscScalar, intent(in) :: x(0:m-1), acols(m,rmax)
11*0ccf82acSMartin Diehl  PetscScalar, intent(out) :: y(m)
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13c96caaccSSatish Balay  PetscInt    i,j
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150113e719SMartin Diehl  do j=1,m
16c96caaccSSatish Balay    y(j) = acols(j,1)*x(icols(j,1))
170113e719SMartin Diehl  end do
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190113e719SMartin Diehl  do i=2,rmax
200113e719SMartin Diehl    do j=1,m
21c96caaccSSatish Balay      y(j) = y(j) + acols(j,i)*x(icols(j,i))
220113e719SMartin Diehl    end do
230113e719SMartin Diehl  end do
240113e719SMartin Diehlend subroutine FortranMultCRL
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