template<typename flt_t>
flt_t max_element2 (nd::Array<flt_t,1,1> const& in) {
  if (boost::size(in) == 1)
    return in[0];
  else {
    flt_t a = max_element2 (in[nd::view(0,boost::size(in)/2)]);
    flt_t b = max_element2 (in[nd::view(boost::size(in)/2)()]);
    return std::max (a, b);
  }
}