[svn-r3196]

Purpose:
    Adding Tutorial to development branch (R 1.4)
Platforms tested:
    IE 5

doc/html/Tutor/examples/h5_extend.c

@@ -0,0 +1,141 @@
+/**************************************************************  
+ *
+ *   This example shows how to work with extendible datasets.
+ *   In the current version of the library a dataset MUST be
+ *   chunked in order to be extendible.  
+ *
+ *   This example is derived from the h5_extend_write.c and 
+ *   h5_read_chunk.c examples that are in the "Introduction 
+ *   to HDF5".
+ *   
+ *************************************************************/
+ 
+#include "hdf5.h"
+
+#define FILE        "ext.h5"
+#define DATASETNAME "ExtendibleArray" 
+#define RANK         2
+
+int
+main (void)
+{
+    hid_t       file;                          /* handles */
+    hid_t       dataspace, dataset;  
+    hid_t       filespace;                   
+    hid_t       cparms;                     
+    hid_t       memspace;
+
+    hsize_t      dims[2]  = { 3, 3};           /* dataset dimensions			
+                                                  at creation time */
+    hsize_t      dims1[2] = { 3, 3};           /* data1 dimensions */ 
+    hsize_t      dims2[2] = { 7, 1};           /* data2 dimensions */  
+
+    hsize_t      maxdims[2] = {H5S_UNLIMITED, H5S_UNLIMITED};
+    hsize_t      size[2];
+    hssize_t     offset[2];
+    hsize_t      i,j;
+    herr_t       status, status_n;                             
+    int          data1[3][3] = { {1, 1, 1},      /* data to write */
+                                 {1, 1, 1},
+                                 {1, 1, 1} };      
+
+    int          data2[7]    = { 2, 2, 2, 2, 2, 2, 2};
+
+    /* Variables used in reading data back */
+    hsize_t      chunk_dims[2] ={2, 5};
+    hsize_t      chunk_dimsr[2];
+    hsize_t      dimsr[2];
+    int          data_out[10][3];
+    int          rank, rank_chunk;
+
+    /* Create the data space with unlimited dimensions. */
+    dataspace = H5Screate_simple (RANK, dims, maxdims); 
+
+    /* Create a new file. If file exists its contents will be overwritten. */
+    file = H5Fcreate (FILE, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);
+
+    /* Modify dataset creation properties, i.e. enable chunking  */
+    cparms = H5Pcreate (H5P_DATASET_CREATE);
+    status = H5Pset_chunk ( cparms, RANK, chunk_dims);
+
+    /* Create a new dataset within the file using cparms
+       creation properties.  */
+    dataset = H5Dcreate (file, DATASETNAME, H5T_NATIVE_INT, dataspace,
+                         cparms);
+
+    /* Extend the dataset. This call assures that dataset is 3 x 3.*/
+    size[0]   = 3; 
+    size[1]   = 3; 
+    status = H5Dextend (dataset, size);
+
+    /* Select a hyperslab  */
+    filespace = H5Dget_space (dataset);
+    offset[0] = 0;
+    offset[1] = 0;
+    status = H5Sselect_hyperslab (filespace, H5S_SELECT_SET, offset, NULL,
+                                  dims1, NULL);  
+
+    /* Write the data to the hyperslab  */
+    status = H5Dwrite (dataset, H5T_NATIVE_INT, dataspace, filespace,
+                       H5P_DEFAULT, data1);
+
+    /* Extend the dataset. Dataset becomes 10 x 3  */
+    dims[0]   = dims1[0] + dims2[0];
+    size[0]   = dims[0];  
+    size[1]   = dims[1]; 
+    status = H5Dextend (dataset, size);
+
+    /* Select a hyperslab  */
+    filespace = H5Dget_space (dataset);
+    offset[0] = 3;
+    offset[1] = 0;
+    status = H5Sselect_hyperslab (filespace, H5S_SELECT_SET, offset, NULL,
+                                  dims2, NULL);  
+
+    /* Define memory space */
+    dataspace = H5Screate_simple (RANK, dims2, NULL); 
+
+    /* Write the data to the hyperslab  */
+    status = H5Dwrite (dataset, H5T_NATIVE_INT, dataspace, filespace,
+                       H5P_DEFAULT, data2);
+
+    /* Close resources */
+    status = H5Dclose (dataset);
+    status = H5Sclose (dataspace);
+    status = H5Sclose (filespace);
+    status = H5Fclose (file);
+
+/****************************************************************
+    Read the data back 
+ ***************************************************************/
+
+    file = H5Fopen (FILE, H5F_ACC_RDONLY, H5P_DEFAULT);
+    dataset = H5Dopen (file, DATASETNAME);
+    filespace = H5Dget_space (dataset);
+    rank = H5Sget_simple_extent_ndims (filespace);
+    status_n = H5Sget_simple_extent_dims (filespace, dimsr, NULL);
+
+    cparms = H5Dget_create_plist (dataset);
+    if (H5D_CHUNKED == H5Pget_layout (cparms))
+    {
+       rank_chunk = H5Pget_chunk (cparms, 2, chunk_dimsr);
+    }
+
+    memspace = H5Screate_simple (rank,dimsr,NULL);
+    status = H5Dread (dataset, H5T_NATIVE_INT, memspace, filespace,
+                      H5P_DEFAULT, data_out);
+    printf("\n");
+    printf("Dataset: \n");
+    for (j = 0; j < dimsr[0]; j++)
+    {
+       for (i = 0; i < dimsr[1]; i++)
+           printf("%d ", data_out[j][i]);
+       printf("\n");
+    }
+
+    status = H5Pclose (cparms);
+    status = H5Dclose (dataset);
+    status = H5Sclose (filespace);
+    status = H5Sclose (memspace);
+    status = H5Fclose (file);
+}