!!$ 
!!$              Parallel Sparse BLAS  version 3.0
!!$    (C) Copyright 2006, 2007, 2008, 2009, 2010, 2012
!!$                       Salvatore Filippone    University of Rome Tor Vergata
!!$                       Alfredo Buttari        CNRS-IRIT, Toulouse
!!$ 
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!!$  
!
! idot.f90
!
! A function formally similar to DDOT but on integers.
! Defined just to have a preprocessed version of vectors. 
!
function idot(n,x,incx,y,incy) result(res)
  use psb_serial_mod
  implicit none 
  integer(psb_ipk_), intent(in) :: n,incx,incy
  integer(psb_ipk_), intent(in) :: x(*), y(*)
  integer(psb_ipk_)  :: res

  integer(psb_ipk_) :: i, ix, iy

  res = izero
  
  if ((n<1).or.(incx<1).or.(incy<1)) return
    
  ix = 1 
  iy = 1
  do i=1,n
    res = res + x(ix)*y(iy)
    ix=ix+incx
    iy=iy+incy
  end do
end function idot