purify::random_updater Namespace Reference

Functions
std::function< bool()>	random_updater (const sopt::mpi::Communicator &comm, const t_int total, const t_int update_size, const std::shared_ptr< bool > update_pointer, const std::string &update_name)

Function Documentation

random_updater()

std::function<bool()> purify::random_updater::random_updater	(	const sopt::mpi::Communicator &	comm,
		const t_int	total,
		const t_int	update_size,
		const std::shared_ptr< bool >	update_pointer,
		const std::string &	update_name
	)

Definition at line 7 of file random_update_factory.cc.

                                                                   {
  if (update_size > comm.size())
    throw std::runtime_error(
        "Number of random updates cannot be greater than number of MPI processors in the "
        "communicator " +
        std::to_string(comm.size()) + " < " + std::to_string(update_size) + " .");
  std::shared_ptr<std::vector<t_int>> ind = std::make_shared<std::vector<t_int>>(total, 0);
  for (t_int i = 0; i < total; i++) (*ind)[i] = i;
  std::random_device rng;
  std::shared_ptr<std::mt19937> urng = std::make_shared<std::mt19937>(rng());
  return [update_pointer, update_size, update_name, ind, comm, urng]() -> bool {
    if (comm.is_root()) {
      std::shuffle(std::begin(*ind), std::end(*ind), *urng);
    };
    *ind = comm.broadcast(*ind);
    *update_pointer = false;
    for (t_int i = 0; i < update_size; i++)
      if (comm.rank() == ind->at(i)) {
        SOPT_DEBUG("Process {} doing {}", comm.rank(), update_name);
        *update_pointer = true;
      }
    return *update_pointer;
  };
}

Referenced by BENCHMARK_DEFINE_F(), and purify::factory::primaldual_factory().