/*
 *   This example copies a hyperslab region of 'SatelliteRange' under
 *   '/All_Data/VIIRS-MOD-GTM-EDR-GEO_All/' to another hyperslab region 
 *   '/SatelliteRange_Subset' under '/All_Data'. It then reads back
 *   the newly created hyperslab region.
 *    Main illustrative functions: H5LTread_region, H5LTcopy_region
*/
#include <stdlib.h>
#include "hdf5.h"
#include "hdf5_hl.h"
#include "h5hl_region.h"

#define filename "GMGTO_npp_d20030125_t0657104_e0659047_b00014_c20090811150425926728_unkn_SCI.h5"

#define PATH_DEST "/Data_Products/SatelliteRange_Subset" /* Full path of the source dataset */
#define PATH_SRC "/All_Data/VIIRS-MOD-GTM-EDR-GEO_All/SatelliteRange" /* Full path to the destination dataset */

#define NRANK 2 /* rank of source and destination dataset */

int main(void)
{
    hid_t file_id;                               /* file identifier */
    hid_t dset_id;                               /* dataset identifier */
    hid_t space_id;                              /* dataspace identifier */
    hsize_t block_coord_src[4] = {3, 51, 7, 53}; /* source's block coordinates (3,51)-(7,53) */
    hsize_t block_coord_dest[4] = {1, 1, 5, 3 }; /* destination's block coordinates (1,1)-(5,3) */
    hsize_t dims[NRANK] = {7,5};                 /* receiving dataset dimensions */
    float rdata[5][3];                           /* buffer to read destination data into */
    int i,j;
    herr_t status;
    /*
     * Open the NPP file.
     */
    file_id = H5Fopen(filename, H5F_ACC_RDWR, H5P_DEFAULT);

    /* 
     * First create the destination dataset "SatelliteRange_Subset" since it does not exist.
     *
     * NOTE: If the destination dataset does not already exist then H5LTcopy_region
     *       will automatically create a destination dataset that is the same size 
     *       and rank of the source data and will, additionally, fill the destination 
     *       block starting at (0,0); thus ignoring the destination's block coordinates.
     */
    space_id = H5Screate_simple(NRANK, dims, NULL);
    dset_id = H5Dcreate2(file_id, PATH_DEST, H5T_NATIVE_FLOAT, space_id, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
    status = H5Sclose(space_id);
    status = H5Fclose(file_id);

    /*
     * Copy a block of the "/All_Data/VIIRS-MOD-GTM-EDR-GEO_All/SatelliteRange"
     * data with block corner coordinates of (3,51)-(7,53) to
     * a subset of the "/Data_Products/SatelliteRange_Subset" with hyperslab
     * coordinates (1,1)-(5,3).
     * 
     */
    status = H5LTcopy_region(filename, PATH_SRC, block_coord_src, filename, PATH_DEST,
  			     block_coord_dest);

    /* 
     *
     * Reads a subset region of "/Data_Products/SatelliteRange_Subset"
     * specified by coordinates (1,1)-(5,3).
     *
     */  
    status = H5LTread_region(filename, PATH_DEST, block_coord_dest, H5T_NATIVE_FLOAT,
 			     rdata);

    printf("Subset of /Data_Products/SatelliteRange_Subset with coordinates ");
    printf("(%d,%d)-(%d,%d):\n",(int)block_coord_dest[0],(int)block_coord_dest[1],
	   (int)block_coord_dest[2],(int)block_coord_dest[3]);
    
    for (i=0; i< 5; i++)
      {
	printf("\n  [ ");
	for (j=0; j< 3; j++) {
	  printf("%f ", rdata[i][j]);
	}
	printf("]");
      }
    printf("\n");

    return 0;
}