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/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 * Copyright by The HDF Group.                                               *
 * Copyright by the Board of Trustees of the University of Illinois.         *
 * All rights reserved.                                                      *
 *                                                                           *
 * This file is part of HDF5.  The full HDF5 copyright notice, including     *
 * terms governing use, modification, and redistribution, is contained in    *
 * the COPYING file, which can be found at the root of the source code       *
 * distribution tree, or in https://support.hdfgroup.org/ftp/HDF5/releases.  *
 * If you do not have access to either file, you may request a copy from     *
 * help@hdfgroup.org.                                                        *
 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */

/*
 *  This example illustrates how to create a dataset that is a 4 x 6
 *  array. It is used in the HDF5 Tutorial.
 */

#include <iostream>
using std::cout;
using std::endl;

#include <string>
#include "H5Cpp.h"
using namespace H5;

const H5std_string      FILE_NAME("h5tutr_extend.h5");
const H5std_string      DATASETNAME("ExtendibleArray");

int main (void)
{
     hsize_t dims[2] = {3,3};           // dataset dimensions at creation
     hsize_t maxdims[2] = {H5S_UNLIMITED, H5S_UNLIMITED}; 
     hsize_t chunk_dims[2] ={2, 5};
     int           data[3][3] = { {1, 1, 1},    // data to write 
                                  {1, 1, 1},
                                  {1, 1, 1} };

     // Variables used in extending and writing to the extended portion of dataset 

     hsize_t size[2];
     hsize_t offset[2];
     hsize_t dimsext[2] = {7, 3};         // extend dimensions 
     int     dataext[7][3] = { {2, 3, 4},
                                      {2, 3, 4},
                                      {2, 3, 4},
                                      {2, 3, 4},
                                      {2, 3, 4},
                                      {2, 3, 4},
                                      {2, 3, 4} };

    // Try block to detect exceptions raised by any of the calls inside it
    try
    {
        // Turn off the auto-printing when failure occurs so that we can
        // handle the errors appropriately
        Exception::dontPrint();

        // Create a new file using the default property lists. 
        H5File file(FILE_NAME, H5F_ACC_TRUNC);

        // Create the data space for the dataset.  Note the use of pointer
        // for the instance 'dataspace'.  It can be deleted and used again
        // later for another dataspace.  An HDF5 identifier can be closed
        // by the destructor or the method 'close()'.
        DataSpace *dataspace = new DataSpace (2, dims, maxdims);

        // Modify dataset creation property to enable chunking
        DSetCreatPropList prop;
        prop.setChunk(2, chunk_dims);

        // Create the chunked dataset.  Note the use of pointer.
        DataSet *dataset = new DataSet(file.createDataSet( DATASETNAME, 
                                 PredType::STD_I32BE, *dataspace, prop) );
 
        // Write data to dataset.
        dataset->write(data, PredType::NATIVE_INT);

        // Extend the dataset. Dataset becomes 10 x 3.
        size[0] = dims[0] + dimsext[0];
        size[1] = dims[1];
        dataset->extend(size); 

        // Select a hyperslab in extended portion of the dataset.
        DataSpace *filespace = new DataSpace(dataset->getSpace ());
        offset[0] = 3;
        offset[1] = 0;
        filespace->selectHyperslab(H5S_SELECT_SET, dimsext, offset);
        
        // Define memory space.
        DataSpace *memspace = new DataSpace(2, dimsext, NULL);

        // Write data to the extended portion of the dataset.
        dataset->write(dataext, PredType::NATIVE_INT, *memspace, *filespace);

        // Close all objects and file.
        prop.close();
        delete filespace;
        delete memspace;
        delete dataspace;
        delete dataset;
        file.close();

        // --------------------------------------- 
        // Re-open the file and read the data back
        // --------------------------------------- 

        int        rdata[10][3];
        int        i,j, rank, rank_chunk;
        hsize_t    chunk_dimsr[2], dimsr[2];

        // Open the file and dataset.
        file.openFile(FILE_NAME, H5F_ACC_RDONLY);
        dataset = new DataSet(file.openDataSet( DATASETNAME)); 

        // Get the dataset's dataspace and creation property list.
        filespace = new DataSpace(dataset->getSpace());
        prop = dataset->getCreatePlist();

        // Get information to obtain memory dataspace.
        rank = filespace->getSimpleExtentNdims();
        herr_t status_n = filespace->getSimpleExtentDims(dimsr);

        if (H5D_CHUNKED == prop.getLayout())
             rank_chunk = prop.getChunk(rank, chunk_dimsr);
        cout << "rank chunk = " << rank_chunk << endl;;

        memspace = new DataSpace(rank, dimsr, NULL);
        dataset->read(rdata, PredType::NATIVE_INT, *memspace, *filespace);
      
        cout << endl;
        for (j = 0; j < dimsr[0]; j++) {
            for (i = 0; i < dimsr[1]; i++)
               cout << " " <<  rdata[j][i];
            cout << endl;
        }

        // Close all objects and file.
        prop.close();
        delete filespace;
        delete memspace;
        delete dataset;
        file.close();
      
    }  // end of try block

    // catch failure caused by the H5File operations
    catch(FileIException error)
    {
        error.printErrorStack();
        return -1;
    }

    // catch failure caused by the DataSet operations
    catch(DataSetIException error)
    {
        error.printErrorStack();
        return -1;
    }

    // catch failure caused by the DataSpace operations
    catch(DataSpaceIException error)
    {
        error.printErrorStack();
        return -1;
    }

    return 0;  // successfully terminated
}