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
|
#include "hdf.h"
#include <math.h>
/*
* In this example we will (1) open the "GridFile" HDF file, (2) attach to
* the "PolarGrid", and (3) subset data from the "Temperature" field.
*/
main()
{
intn i, j, status;
int32 gdfid, GDid, regionID, size, dims[8], ntype, rank;
float32 *datbuf32;
float64 cornerlon[2], cornerlat[2];
float64 *datbuf64, upleft[2], lowright[2];
/*
* Open the HDF grid file, "GridFile.hdf".
*/
gdfid = GDopen("GridFile_created_with_hadeos_sample_file_writer_of_HDFEOS2_version_219_or_higher_release.hdf", DFACC_RDWR);
if (gdfid != -1)
{
GDid = GDattach(gdfid, "PolarGrid");
if (GDid != -1)
{
cornerlon[0] = 57.;
cornerlat[0] = 23.;
cornerlon[1] = 59.;
cornerlat[1] = 35.;
cornerlon[0] = 10.;
cornerlat[0] = 80.;
cornerlon[1] = 80.;
cornerlat[1] = 10.;
regionID = GDdefboxregion(GDid, cornerlon, cornerlat);
if (regionID == -1)
{
printf("\t\tError: Cannot define subsetting region for grid \"PolarGrid\"\n");
return -1;
}
status = GDregioninfo(GDid, regionID, "Temperature", &ntype,
&rank, dims, &size, upleft, lowright);
if (status == -1)
{
printf("\t\tError: Cannot get region info for field \"Temperature\" of grid \"PolarGrid\"\n");
return -1;
}
printf("size: %d\n",size);
datbuf32 = (float32 *) calloc(size, 1);
status = GDextractregion(GDid, regionID, "Temperature",
datbuf32);
if (status == -1)
{
printf("\t\tError: Cannot extract region info for field \"Temperature\" of grid \"PolarGrid\"\n");
return -1;
}
free(datbuf32);
}
}
GDdetach(GDid);
GDclose(gdfid);
return 0;
}
|
