mat_wcopy Subroutine

subroutine mat_wcopy(number_of_values,xr,xi,incx,yr,yi,incy)
integer,intent(in)          :: number_of_values
doubleprecision,intent(in)  :: xr(*)
doubleprecision,intent(in)  :: xi(*)
integer,intent(in)          :: incx
doubleprecision,intent(out) :: yr(*)
doubleprecision,intent(out) :: yi(*)
integer,intent(in)          :: incy

integer                     :: ix
integer                     :: iy
integer                     :: i
   if (number_of_values .gt. 0) then
      ix = 1
      iy = 1
      if (incx.lt.0) ix = (-number_of_values+1)*incx + 1
      if (incy.lt.0) iy = (-number_of_values+1)*incy + 1
      do i = 1, number_of_values
         yr(iy) = xr(ix)
         yi(iy) = xi(ix)
         ix = ix + incx
         iy = iy + incy
      enddo
   endif
end subroutine mat_wcopy