/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * 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 read/write a subset of data (a slab) * from/to a dataset in an HDF5 file. It is used in the HDF5 Tutorial. */ #include "hdf5.h" #define FILE "subset.h5" #define DATASETNAME "IntArray" #define RANK 2 #define DIM0_SUB 3 /* subset dimensions */ #define DIM1_SUB 4 #define DIM0 8 /* size of dataset */ #define DIM1 10 int main (void) { hsize_t dims[2], dimsm[2]; int data[DIM0][DIM1]; /* data to write */ int sdata[DIM0_SUB][DIM1_SUB]; /* subset to write */ int rdata[DIM0][DIM1]; /* buffer for read */ hid_t file_id, dataset_id; /* handles */ hid_t dataspace_id, memspace_id; herr_t status; hsize_t count[2]; /* size of subset in the file */ hsize_t offset[2]; /* subset offset in the file */ hsize_t stride[2]; hsize_t block[2]; int i, j; /***************************************************************** * Create a new file with default creation and access properties.* * Then create a dataset and write data to it and close the file * * and dataset. * *****************************************************************/ file_id = H5Fcreate (FILE, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT); dims[0] = DIM0; dims[1] = DIM1; dataspace_id = H5Screate_simple (RANK, dims, NULL); dataset_id = H5Dcreate2 (file_id, DATASETNAME, H5T_STD_I32BE, dataspace_id, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT); for (j = 0; j < DIM0; j++) { for (i = 0; i < DIM1; i++) if (i< (DIM1/2)) data[j][i] = 1; else data[j][i] = 2; } status = H5Dwrite (dataset_id, H5T_NATIVE_INT, H5S_ALL, H5S_ALL, H5P_DEFAULT, data); printf ("\nData Written to File:\n"); for (i = 0; i<DIM0; i++){ for (j = 0; j<DIM1; j++) printf (" %i", data[i][j]); printf ("\n"); } status = H5Sclose (dataspace_id); status = H5Dclose (dataset_id); status = H5Fclose (file_id); /***************************************************** * Reopen the file and dataset and write a subset of * * values to the dataset. *****************************************************/ file_id = H5Fopen (FILE, H5F_ACC_RDWR, H5P_DEFAULT); dataset_id = H5Dopen2 (file_id, DATASETNAME, H5P_DEFAULT); /* Specify size and shape of subset to write. */ offset[0] = 1; offset[1] = 2; count[0] = DIM0_SUB; count[1] = DIM1_SUB; stride[0] = 1; stride[1] = 1; block[0] = 1; block[1] = 1; /* Create memory space with size of subset. Get file dataspace and select subset from file dataspace. */ dimsm[0] = DIM0_SUB; dimsm[1] = DIM1_SUB; memspace_id = H5Screate_simple (RANK, dimsm, NULL); dataspace_id = H5Dget_space (dataset_id); status = H5Sselect_hyperslab (dataspace_id, H5S_SELECT_SET, offset, stride, count, block); /* Write a subset of data to the dataset, then read the entire dataset back from the file. */ printf ("\nWrite subset to file specifying:\n"); printf (" offset=1x2 stride=1x1 count=3x4 block=1x1\n"); for (j = 0; j < DIM0_SUB; j++) { for (i = 0; i < DIM1_SUB; i++) sdata[j][i] = 5; } status = H5Dwrite (dataset_id, H5T_NATIVE_INT, memspace_id, dataspace_id, H5P_DEFAULT, sdata); status = H5Dread (dataset_id, H5T_NATIVE_INT, H5S_ALL, H5S_ALL, H5P_DEFAULT, rdata); printf ("\nData in File after Subset is Written:\n"); for (i = 0; i<DIM0; i++){ for (j = 0; j<DIM1; j++) printf (" %i", rdata[i][j]); printf ("\n"); } status = H5Sclose (memspace_id); status = H5Sclose (dataspace_id); status = H5Dclose (dataset_id); status = H5Fclose (file_id); }