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#include "hdf.h"
#include "HdfEosDef.h"
#include <math.h>
/*
* In this example we will open an HDF file and create UTM and Polar
* Stereographic grid structures within the file.
*/
main()
{
intn status, i, j;
int32 gdfid, GDid, GDid2, GDid3, dummy;
int32 xdim, ydim, zonecode, projcode, spherecode;
float64 projparm[16], uplft[2], lowrgt[2];
float64 EHconvAng();
char *ptr = NULL;
/*
* We first open the HDF grid file, "GridFile.hdf". Because this file
* does not already exist, we use the DFACC_CREATE access code in the
* open statement. The GDopen routine returns the grid file id, gdfid,
* which is used to identify the file in subsequent routines in the
* library.
*/
/* a long filename (> 80 characters) is used to test long file names ( > 80 characters)
that caused problem in version 2.18
*/
gdfid = GDopen("GridFile_created_with_hadeos_sample_file_writer_of_HDFEOS2_version_219_or_higher_release.hdf", DFACC_CREATE);
if (gdfid == -1)
{
printf("\t\tError: Cannot open file \"GridFile.hdf\"\n");
return -1;
}
/*
* Create UTM Grid
*
* Region is bounded by 54 E and 60 E longitude and 20 N and 30 N latitude.
* UTM Zone 40
*
* Use default spheriod (Clarke 1866 - spherecode = 0)
*
* Grid into 120 bins along x-axis and 200 bins along y-axis
* (approx 3' by 3' bins)
*/
zonecode = 40;
spherecode = 0;
/* Upper Left and Lower Right points in meters */
/* ------------------------------------------- */
uplft[0] = 210584.50041;
uplft[1] = 3322395.95445;
lowrgt[0] = 813931.10959;
lowrgt[1] = 2214162.53278;
xdim = 120;
ydim = 200;
GDid = GDcreate(gdfid, "UTMGrid", xdim, ydim, uplft, lowrgt);
if (GDid == -1)
{
printf("\t\tError: Cannot create grid \"UTMGrid\"\n");
return -1;
}
status = GDdefproj(GDid, GCTP_UTM, zonecode, spherecode, projparm);
if (status == -1)
{
printf("\t\tError: Cannot define UTM projection for grid\"UTMGrid\"\n");
return -1;
}
/* Define "Time" Dimension */
status = GDdefdim(GDid, "Time", 10);
if (status == -1)
{
printf("\t\tError: Cannot define dim \"Time\"\n");
return -1;
}
/*
* Create polar stereographic grid
*
* Northern Hemisphere (True Scale at 90 N, 0 Longitude below pole)
*
* Use International 1967 spheriod (spherecode = 3)
*
* Grid into 100 bins along x-axis and y-axis
*/
spherecode = 3;
/* Define GCTP Projection Parameters */
/* --------------------------------- */
for (i = 0; i < 16; i++)
projparm[i] = 0;
/* Set Longitude below pole & true scale in DDDMMMSSS.SSS format) */
projparm[4] = 0.0;
projparm[5] = 90000000.00;
xdim = 100;
ydim = 100;
GDid2 = GDcreate(gdfid, "PolarGrid", xdim, ydim, NULL, NULL);
if (GDid2 == -1)
{
printf("\t\tError: Cannot create grid \"PolarGrid\"\n");
return -1;
}
status = GDdefproj(GDid2, GCTP_PS, dummy, spherecode, projparm);
if (status == -1)
{
printf("\t\tError: Cannot define PS projection for grid\"PolarGrid\"\n");
return -1;
}
status = GDdeforigin(GDid2, HDFE_GD_LR);
if (status == -1)
{
printf("\t\tError: Cannot define origin for grid\"PolarGrid\"\n");
return -1;
}
/* Define "Bands" Dimension */
status = GDdefdim(GDid2, "Bands", 3);
if (status == -1)
{
printf("\t\tError: Cannot define dim \"Bands\"\n");
return -1;
}
/*
* Create geographic (linear scale) grid
*
* 0 - 15 degrees longitude, 20 - 30 degrees latitude
*
*/
xdim = 60;
ydim = 40;
uplft[0] = EHconvAng(0., HDFE_DEG_DMS);
uplft[1] = EHconvAng(30., HDFE_DEG_DMS);
lowrgt[0] = EHconvAng(15., HDFE_DEG_DMS);
lowrgt[1] = EHconvAng(20., HDFE_DEG_DMS);
GDid3 = GDcreate(gdfid, "GEOGrid", xdim, ydim, uplft, lowrgt);
if (status == -1)
{
printf("\t\tError: Cannot create GEO grid\"GEOGrid\"\n");
return -1;
}
status = GDdefproj(GDid3, GCTP_GEO, dummy, dummy, NULL);
if (status == -1)
{
printf("\t\tError: Cannot define GEO projection for grid\"GEOGrid\"\n");
return -1;
}
/*
* We now close the grid interface with the GDdetach routine. This step
* is necessary to properly store the grid information within the file
* AND SHOULD BE DONE BEFORE WRITING OR READING DATA TO OR FROM THE FIELD.
*/
GDdetach(GDid);
GDdetach(GDid2);
GDdetach(GDid3);
/*
* Finally, we close the grid file using the GDclose routine. This will
* release the grid file handles established by GDopen.
*/
GDclose(gdfid);
return 0;
}
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