[svn-r26562] Added examples for percival use case.

1 files changed, 245 insertions, 0 deletions

diff --git a/examples/h5_vds-percival.c b/examples/h5_vds-percival.c
new file mode 100644
index 0000000..c065368
--- /dev/null
+++ b/examples/h5_vds-percival.c
@@ -0,0 +1,245 @@
+/************************************************************
+
+  This example illustrates the concept of the virtual dataset.
+  Percival use case. Every fifth 10x10 plane in VDS is stored in 
+  the corresponding 3D unlimited dataset. 
+  EIP: For now we will use finite dimension.
+  There are 4 source datasets total.
+  This file is intended for use with HDF5 Library version 1.10
+
+ ************************************************************/
+/* EIP Add link to the picture */
+
+#include "hdf5.h"
+#include <stdio.h>
+#include <stdlib.h>
+
+#define FILE         "vds-percival.h5"
+#define DATASET      "VDS-Percival"
+/* later
+#define VDSDIM0       H5S_UNLIMITED 
+*/
+#define VDSDIM0       40
+#define VDSDIM1       10 
+#define VDSDIM2       10 
+/* later
+#define DIM0          H5S_UNLIMITED 
+*/
+#define DIM0          10 
+#define DIM1          10 
+#define DIM2          10 
+#define RANK          3 
+#define PLANE_STRIDE  4
+
+const char *SRC_FILE[] = {
+    "a.h5",
+    "b.h5",
+    "c.h5",
+    "d.h5"
+};
+
+const char *SRC_DATASET[] = {
+    "A",
+    "B",
+    "C",
+    "D"
+};
+
+int
+main (void)
+{
+    hid_t        file, src_space, vspace,
+                 dset;                       /* Handles */
+    hid_t        dcpl;
+    herr_t       status;
+    hsize_t      vdsdims[3] = {VDSDIM0, VDSDIM1, VDSDIM2},
+                 vdsdims_max[3] = {VDSDIM0, VDSDIM1, VDSDIM2}, 
+                 dims[3] = {DIM0, DIM1, DIM2},
+                 dims_max[3] = {DIM0, DIM1, DIM2},
+                 start[3],                   /* Hyperslab start parameter for VDS */
+                 src_start[3],               /* Hyperslab start parameter for source dataset */
+                 stride[3],
+                 count[3],
+                 src_count[3],
+                 block[3];
+    hsize_t      start_out[3],               /* Hyperslab parameter out */
+                 stride_out[3],
+                 count_out[3],
+                 block_out[3];
+    int          i, j;
+    H5D_layout_t layout;                     /* Storage layout */
+    size_t       num_map;                    /* Number of mappings */
+    ssize_t      len;                        /* Length of the string; also a return value */
+    char         *filename;
+    char         *dsetname;
+    int          wdata[DIM0*DIM1*DIM2];
+
+    /*
+     * Create source files and datasets. This step is optional.
+     */
+    for (i=0; i < PLANE_STRIDE; i++) {
+        /*
+         * Initialize data for i-th source dataset.
+         */
+        for (j = 0; j < DIM0*DIM1*DIM2; j++) wdata[j] = i+1;
+
+        /*
+         * Create the source files and  datasets. Write data to each dataset and 
+         * close all resources.
+         */
+
+        file = H5Fcreate (SRC_FILE[i], H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);
+        src_space = H5Screate_simple (RANK, dims, NULL);
+        dset = H5Dcreate (file, SRC_DATASET[i], H5T_NATIVE_INT, src_space, H5P_DEFAULT,
+                    H5P_DEFAULT, H5P_DEFAULT);
+        status = H5Dwrite (dset, H5T_NATIVE_INT, H5S_ALL, H5S_ALL, H5P_DEFAULT,
+                    wdata);
+        status = H5Sclose (src_space);
+        status = H5Dclose (dset);
+        status = H5Fclose (file);
+    }    
+
+    file = H5Fcreate (FILE, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);
+
+    /* Create VDS dataspace.  */
+    vspace = H5Screate_simple (RANK, vdsdims, vdsdims_max);
+
+    /* Create dataspaces for the source dataset. */
+    src_space = H5Screate_simple (RANK, dims, dims_max);
+
+    /* Create VDS creation property */
+    dcpl = H5Pcreate (H5P_DATASET_CREATE);
+     
+    /* Initialize hyperslab values */
+
+    start[0] = 0;
+    start[1] = 0;
+    start[2] = 0;
+    src_start[0] = 0;
+    src_start[1] = 0;
+    src_start[2] = 0;
+    stride[0] = PLANE_STRIDE; /* we will select every fifth plane in VDS */
+    stride[1] = 1;
+    stride[2] = 1;
+/* later
+    count[0] = H5S_UNLIMITED;
+*/
+    count[0] = VDSDIM0/4;
+    count[1] = 1;
+    count[2] = 1;
+/* later
+    src_count[0] = H5S_UNLIMITED;
+*/
+    src_count[0] = DIM0;
+    src_count[1] = 1;
+    src_count[2] = 1;
+    block[0] = 1;
+    block[1] = DIM1;
+    block[2] = DIM2;
+
+    /* 
+     * Build the mappings 
+     *
+     */
+    for (i=0; i < PLANE_STRIDE; i++) {
+        status = H5Sselect_hyperslab (vspace, H5S_SELECT_SET, start, stride, count, block);
+        status = H5Sselect_hyperslab (src_space, H5S_SELECT_SET, src_start, NULL, src_count, block);
+        status = H5Pset_virtual (dcpl, vspace, SRC_FILE[i], SRC_DATASET[i], src_space);
+        start[0]++; 
+    } 
+
+
+   /* Create a virtual dataset */
+      dset = H5Dcreate (file, DATASET, H5T_NATIVE_INT, vspace, H5P_DEFAULT,
+                  dcpl, H5P_DEFAULT);
+      status = H5Sclose (vspace);
+      status = H5Sclose (src_space);
+      status = H5Dclose (dset);
+      status = H5Fclose (file);    
+     
+    /*
+     * Now we begin the read section of this example.
+     */
+
+    /*
+     * Open file and dataset using the default properties.
+     */
+    file = H5Fopen (FILE, H5F_ACC_RDONLY, H5P_DEFAULT);
+    dset = H5Dopen (file, DATASET, H5P_DEFAULT);
+
+    /*
+     * Get creation property list and mapping properties.
+     */
+    dcpl = H5Dget_create_plist (dset);
+
+    /*
+     * Get storage layout.
+     */
+    layout = H5Pget_layout (dcpl);
+
+    if (H5D_VIRTUAL == layout) 
+        printf(" Dataset has a virtual layout \n");
+    else
+        printf(" Wrong layout found \n");
+
+     /*
+      * Find number of mappings.
+      */
+     status = H5Pget_virtual_count (dcpl, &num_map);
+     printf(" Number of mappings is %d\n", num_map);
+
+     /* 
+      * Get mapping parameters for each mapping.
+      */
+      for (i = 0; i < (int)num_map; i++) {   
+      printf(" Mapping %d \n", i);
+      printf("         Selection in the virtual dataset \n");
+      /* Get selection in the virttual  dataset */
+          vspace = H5Pget_virtual_vspace (dcpl, (size_t)i);
+          if (H5Sget_select_type(vspace) == H5S_SEL_HYPERSLABS) { 
+              if (H5Sis_regular_hyperslab(vspace)) {
+                   status = H5Sget_regular_hyperslab (vspace, start_out, stride_out, count_out, block_out);
+                   printf("         start  = [%llu, %llu, %llu] \n", (unsigned long long)start_out[0], (unsigned long long)start_out[1], (unsigned long long)start_out[2]);
+                   printf("         stride = [%llu, %llu, %llu] \n", (unsigned long long)stride_out[0], (unsigned long long)stride_out[1], (unsigned long long)stride_out[2]);
+                   printf("         count  = [%llu, %llu, %llu] \n", (unsigned long long)count_out[0], (unsigned long long)count_out[1], (unsigned long long)count_out[2]);
+                   printf("         block  = [%llu, %llu, %llu] \n", (unsigned long long)block_out[0], (unsigned long long)block_out[1], (unsigned long long)block_out[2]);
+               }
+          }
+      /* Get source file name */
+          len = H5Pget_virtual_filename (dcpl, (size_t)i, NULL, 0);
+          filename = (char *)malloc((size_t)len*sizeof(char)+1);
+          H5Pget_virtual_filename (dcpl, (size_t)i, filename, len+1);
+          printf("         Source filename %s\n", filename);
+
+      /* Get source dataset name */
+          len = H5Pget_virtual_dsetname (dcpl, (size_t)i, NULL, 0);
+          dsetname = (char *)malloc((size_t)len*sizeof(char)+1);
+          H5Pget_virtual_dsetname (dcpl, (size_t)i, dsetname, len+1);
+          printf("         Source dataset name %s\n", dsetname);
+
+      /* Get selection in the source dataset */
+          printf("         Selection in the source dataset \n");
+          src_space = H5Pget_virtual_srcspace (dcpl, (size_t)i);
+          if (H5Sget_select_type(src_space) == H5S_SEL_HYPERSLABS) {
+              if (H5Sis_regular_hyperslab(src_space)) {
+                   status = H5Sget_regular_hyperslab (src_space, start_out, stride_out, count_out, block_out);
+                   printf("         start  = [%llu, %llu, %llu] \n", (unsigned long long)start_out[0], (unsigned long long)start_out[1], (unsigned long long)start_out[2]);
+                   printf("         stride = [%llu, %llu, %llu] \n", (unsigned long long)stride_out[0], (unsigned long long)stride_out[1], (unsigned long long)stride_out[2]);
+                   printf("         count  = [%llu, %llu, %llu] \n", (unsigned long long)count_out[0], (unsigned long long)count_out[1], (unsigned long long)count_out[2]);
+                   printf("         block  = [%llu, %llu, %llu] \n", (unsigned long long)block_out[0], (unsigned long long)block_out[1], (unsigned long long)block_out[2]);
+               }
+          }
+          H5Sclose(vspace);
+          H5Sclose(src_space);
+          free(filename);
+          free(dsetname);
+      }
+    /*
+     * Close and release resources.
+     */
+    status = H5Pclose (dcpl);
+    status = H5Dclose (dset);
+    status = H5Fclose (file);
+    return 0;
+}
+