parallel_hdf5_write_dataset.cpp

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/*
 *  Copyright (c), 2017, Adrien Devresse
 *
 *  Distributed under the Boost Software License, Version 1.0.
 *    (See accompanying file LICENSE_1_0.txt or copy at
 *          http://www.boost.org/LICENSE_1_0.txt)
 *
 */
#include <iostream>
#include <string>
#include <vector>

#include <mpi.h>

#include <highfive/H5DataSet.hpp>
#include <highfive/H5DataSpace.hpp>
#include <highfive/H5File.hpp>

const std::string FILE_NAME("parallel_dataset_example.h5");
const std::string DATASET_NAME("dset");

//
// simple example to write a dataset with Parallel HDF5 with MPI-IO
//
// The dataset is written from several MPI node in parallel
//
//
int main(int argc, char** argv) {
    int mpi_rank, mpi_size;

    // initialize MPI
    MPI_Init(&argc, &argv);
    MPI_Comm_size(MPI_COMM_WORLD, &mpi_size);
    MPI_Comm_rank(MPI_COMM_WORLD, &mpi_rank);

    using namespace HighFive;
    try {

        // open a new file with the MPI IO driver for parallel Read/Write
        File file(FILE_NAME, File::ReadWrite | File::Create | File::Truncate,
                  MPIOFileDriver(MPI_COMM_WORLD, MPI_INFO_NULL));

        // we define the size of our dataset to
        //  lines : total number of mpi_rank
        //  columns : 2
        std::vector<size_t> dims(2);
        dims[0] = std::size_t(mpi_size);
        dims[1] = 2;

        // Create the dataset
        DataSet dataset =
            file.createDataSet<double>(DATASET_NAME, DataSpace(dims));

        // Each node want to write its own rank two time in
        // its associated row
        int data[1][2] = {{mpi_rank, mpi_rank}};

        // write it to the associated mpi_rank
        dataset.select({std::size_t(mpi_rank), 0}, {1, 2}).write(data);

    } catch (Exception& err) {
        // catch and print any HDF5 error
        std::cerr << err.what() << std::endl;
        MPI_Abort(MPI_COMM_WORLD, 1);
    }

    MPI_Finalize();
    return 0; // successfully terminated
}