mat_iwamax Function

integer function mat_iwamax(n,xr,xi,incx)

! ident_41="@(#)M_LA::mat_iwamax(3fp):index of norminf(x)"

integer         :: n
doubleprecision :: xr(*)
doubleprecision :: xi(*)
integer         :: incx
doubleprecision :: s
doubleprecision :: p
integer         :: i, k
integer         :: ix

   k = 0
   if (n .gt. 0) then
      k = 1
      s = 0.0d0
      ix = 1
      do i = 1, n
         p = dabs(xr(ix)) + dabs(xi(ix))
         if (p .gt. s) k = i
         if (p .gt. s) s = p
         ix = ix + incx
      enddo
   endif
   mat_iwamax = k
end function mat_iwamax