1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
|
/************************************************************
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 */
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 = H5Dcreate2 (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;
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
*
*/
status = H5Sselect_hyperslab (src_space, H5S_SELECT_SET, start, NULL, src_count, block);
for (i=0; i < PLANE_STRIDE; i++) {
status = H5Sselect_hyperslab (vspace, H5S_SELECT_SET, start, stride, count, block);
status = H5Pset_virtual (dcpl, vspace, SRC_FILE[i], SRC_DATASET[i], src_space);
start[0]++;
}
H5Sselect_none(vspace);
/* Create a virtual dataset */
dset = H5Dcreate2 (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 = H5Dopen2 (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 %lu\n", (unsigned long)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;
}
|
