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
|
/*
* Example illustrates the use of SZIP compression in HDF5
*/
#include <stdio.h>
#include "hdf5.h"
#define NX 500
#define NY 600
#define CH_NX 100
#define CH_NY 25
static void initialize(void);
static int compare(void);
static float buf[NX][NY];
static float buf_r[NX][NY];
static const char* filename = "test.h5";
static int
writeszip()
{
hid_t file;
hid_t dataset32;
hid_t properties;
hid_t lcpl_id, dapl_id;
hid_t data_space;
hsize_t dims[2], chunk_size[2];
unsigned szip_options_mask;
unsigned szip_pixels_per_block;
/*
* Create a new file using read/write access, default file
* creation properties, and default file access properties.
*/
file = H5Fcreate (filename, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);
/* Describe the size of the array. */
dims[0] = NX;
dims[1] = NY;
data_space = H5Screate_simple (2, dims, NULL);
/*
* Set the dataset creation property list to specify that
* the raw data is to be partitioned into 100x100 element
* chunks and that each chunk is to be compressed.
*/
chunk_size[0] = CH_NX;
chunk_size[1] = CH_NY;
properties = H5Pcreate (H5P_DATASET_CREATE);
H5Pset_chunk (properties, 2, chunk_size);
/*
* Set parameters for SZIP compression; check the description of
* the H5Pset_szip function in the HDF5 Reference Manual for more
* information.
*/
szip_options_mask=H5_SZIP_NN_OPTION_MASK;
szip_pixels_per_block=32;
H5Pset_szip (properties, szip_options_mask, szip_pixels_per_block);
/*
* Create a new dataset within the file. The datatype
* and data space describe the data on disk, which may
* be different from the format used in the application's
* memory.
*/
lcpl_id = H5Pcreate (H5P_LINK_CREATE);
dapl_id = H5Pcreate (H5P_DATASET_ACCESS);
dataset32 = H5Dcreate (file, "datasetF32", H5T_NATIVE_FLOAT, data_space, lcpl_id, properties, dapl_id);
/*
* Write the array to the file. The datatype and dataspace
* describe the format of the data in the `buf' buffer.
* The raw data is translated to the format required on disk,
* as defined above. We use default raw data transfer properties.
*/
H5Dwrite (dataset32, H5T_NATIVE_FLOAT, H5S_ALL, H5S_ALL,
H5P_DEFAULT, buf);
H5Sclose (data_space);
H5Pclose(lcpl_id);
H5Pclose(dapl_id);
H5Pclose (properties);
H5Dclose (dataset32);
H5Fclose (file);
return 1;
}
static int
readszip()
{
hid_t file;
hid_t dataset32;
hid_t properties;
int errcnt = 0;
file = H5Fopen (filename, H5F_ACC_RDONLY, H5P_DEFAULT);
properties = H5Pcreate(H5P_DATASET_ACCESS);
dataset32 = H5Dopen(file, "datasetF32", properties);
/*
* Read the array. This is similar to writing data,
* except the data flows in the opposite direction.
* Note: Decompression is automatic.
*/
H5Dread(dataset32, H5T_NATIVE_FLOAT, H5S_ALL, H5S_ALL, H5P_DEFAULT, buf_r);
errcnt = compare();
H5Pclose(properties);
H5Dclose (dataset32);
H5Fclose (file);
return (errcnt==0 ? 1 : 0);
}
static int
compare(void)
{
int i,j;
int errs = 0;
/* Do comparison */
for (i=0; i < NX; i++) {
for (j=0; j < NY; j++) {
if(buf[i][j] != buf_r[i][j]) {
errs++;
printf("mismatch: [%d][%d]: write = %f read=%f\n",
i,j,buf[i][j],buf_r[i][j]);
}
}
}
return errs;
}
static void
initialize(void)
{
int i, j;
/* Initialize data buffer with some bogus data. */
for(i=0; i < NX; i++) {
for(j=0; j < NY; j++) {
buf[i][j] = (float)(i + j);
}
}
}
int
main(int argc, char** argv)
{
int extfile = 0;
if(argc > 1) {
filename = argv[1];
extfile = 1;
}
initialize();
if(!extfile) {
if(!writeszip()) {
fprintf(stderr,"writeszip failed.\n");
goto fail;
}
}
if(!readszip()) {
fprintf(stderr,"openfile failed.\n");
goto fail;
}
fprintf(stderr,"***PASS\n");
return 0;
fail:
fprintf(stderr,"***FAIL\n");
return 1;
}
|
