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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 files COPYING and Copyright.html. COPYING can be found at the root *
+ * of the source code distribution tree; Copyright.html can be found at the *
+ * root level of an installed copy of the electronic HDF5 document set and *
+ * is linked from the top-level documents page. It can also be found at *
+ * http://hdfgroup.org/HDF5/doc/Copyright.html. 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 = H5Dcreate (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 = H5Dopen (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);
+
+}