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#include "mfhdf.h"
/*
* In this example we will (1) open an HDF file, (2) create the swath
* interface within the file and (3) define the swath field dimensions.
*/
main()
{
intn status, i, j;
int32 swfid, SWid, indx[12]={0,1,3,6,7,8,11,12,14,24,32,39};
/*
* We first open the HDF swath file, "SwathFile.hdf". Because this file
* does not already exist, we use the DFACC_CREATE access code in the
* open statement. The SWopen routine returns the swath file id, swfid,
* 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
*/
swfid = SWopen("SwathFile_created_with_hadeos_sample_file_writer_of_HDFEOS2_version_219_or_higher_release.hdf", DFACC_CREATE);
if (swfid == -1)
{
printf("\t\tError: Cannot open file \"SwathFile.hdf\"\n");
return -1;
}
/*
* The first of these, SWcreate, creates the swath, "Swath1", within the
* file designated by the file id, swfid. It returns the swath id, SWid,
* which identifies the swath in subsequent routines. We will show how
* to define, write and read field swaths in later programs.
*/
SWid = SWcreate(swfid, "Swath1");
if (SWid == -1)
{
printf("\t\tError: Cannot create swath \"Swath1\"\n");
return -1;
}
/*
* Typically, many fields within a swath share the same dimension. The
* swath interface therefore provides a way of defining dimensions that
* will then be used to define swath fields. A dimension is defined with
* a name and a size and is connected to the particular swath through the
* swath id. In this example, we define the geolocation track and
* cross track dimensions with size 20 and 10 respectively and two
* dimensions corresponding to these but with twice the resolution.
* We also define a dimension corresponding to a number of spectal
* bands.
*/
status = SWdefdim(SWid, "GeoTrack", 20);
if (status == -1)
{
printf("\t\tError: Cannot define dim \"GeoTrack\"\n");
return -1;
}
status = SWdefdim(SWid, "GeoXtrack", 10);
if (status == -1)
{
printf("\t\tError: Cannot define dim \"GeoXtrack\"\n");
return -1;
}
status = SWdefdim(SWid, "Res2tr", 40);
if (status == -1)
{
printf("\t\tError: Cannot define dim \"Res2tr\"\n");
return -1;
}
status = SWdefdim(SWid, "Res2xtr", 20);
if (status == -1)
{
printf("\t\tError: Cannot define dim \"Res2xtr\"\n");
return -1;
}
status = SWdefdim(SWid, "Bands", 15);
if (status == -1)
{
printf("\t\tError: Cannot define dim \"Bands\"\n");
return -1;
}
status = SWdefdim(SWid, "IndxTrack", 12);
if (status == -1)
{
printf("\t\tError: Cannot define dim \"IndxTrack\"\n");
return -1;
}
/* Define Unlimited Dimension */
/* -------------------------- */
status = SWdefdim(SWid, "Unlim", NC_UNLIMITED);
if (status == -1)
{
printf("\t\tError: Cannot define dim \"Unlim\"\n");
return -1;
}
/*
* Once the dimensions are defined, the relationship (mapping) between the
* geolocation dimensions, such as track and cross track, and the data
* dimensions, must be established. This is done through the SWdefdimmap
* routine. It takes as input the swath id, the names of the dimensions
* designating the geolocation and data dimensions, respectively, and the
* offset and increment defining the relation.
*
* In the first example we relate the "GeoTrack" and "Res2tr" dimensions
* with an offset of 0 and an increment of 2. Thus the ith element of
* "Geotrack" corresponds to the 2 * ith element of "Res2tr".
*
* In the second example, the ith element of "GeoXtrack" corresponds to the
* 2 * ith + 1 element of "Res2xtr".
*
* Note that there is no relationship between the geolocation dimensions
* and the "Bands" dimension.
*/
status = SWdefdimmap(SWid, "GeoTrack", "Res2tr", 0, 2);
if (status == -1)
{
printf("\t\tError: Cannot define dim map batween \"GeoTrack\" and \"Res2tr\"\n");
return -1;
}
status = SWdefdimmap(SWid, "GeoXtrack", "Res2xtr", 1, 2);
if (status == -1)
{
printf("\t\tError: Cannot define dim map batween \"GeoXtrack\" and \"Res2xtr\"\n");
return -1;
}
/* Define Indexed Mapping */
status = SWdefidxmap(SWid, "IndxTrack", "Res2tr", indx);
if (status == -1)
{
printf("\t\tError: Cannot define dim map batween \"IndxTrack\" and \"Res2tr\"\n");
return -1;
}
/*
* We now close the swath interface with the SWdetach routine. This step
* is necessary to properly store the swath information within the file.
*/
status = SWdetach(SWid);
if (status == -1)
{
printf("\t\tError: Cannot detach SWid\n");
return -1;
}
/*
* Finally, we close the swath file using the SWclose routine. This will
* release the swath file handles established by SWopen.
*/
status = SWclose(swfid);
if (status == -1)
{
printf("\t\tError: Cannot close hdf file.\n");
return -1;
}
return 0;
}
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