netcdf-c/examples/C/simple.c
2010-06-03 13:23:50 +00:00

75 lines
1.8 KiB
C

/* This example program is part of Unidata's netCDF library for
scientific data access.
How about a short, but meaningful, netCDF program?
Ed Hartnett, 6/19/4
$Id: simple.c,v 1.1 2004/07/26 14:04:42 ed Exp $
*/
#include <netcdf.h>
#include <stdio.h>
#include <string.h>
/* This macro handles errors by outputting a message to stdout and
then exiting. */
#define NC_EXAMPLE_ERROR 2 /* This is the exit code for failure. */
#define BAIL(e) do { \
printf("Bailing out in file %s, line %d, error:%s.\n", \
__FILE__, __LINE__, nc_strerror(e)); \
return NC_EXAMPLE_ERROR; \
} while (0)
#define NUMDIMS 2
#define NUMVARS 1
#define CELSIUS "celsius"
#define LAT_LEN 3
#define LON_LEN 2
int
main()
{
int ncid, temp_varid, dimids[NUMDIMS];
float temp[LAT_LEN][LON_LEN], *fp;
int i, res;
/* Create a bunch of phoney data so we have something to write in
the example file. */
for (fp=(float *)temp, i=0; i<LAT_LEN*LON_LEN; i++)
*fp++ = 10. + i/10.;
/* Create the netCDF file. */
if ((res = nc_create("short.nc", NC_CLOBBER, &ncid)))
BAIL(res);
/* Define dimensions. */
if ((res = nc_def_dim(ncid, "latitude", LAT_LEN, dimids)))
BAIL(res);
if ((res = nc_def_dim(ncid, "longitude", LON_LEN, &dimids[1])))
BAIL(res);
/* Define the variable. */
if ((res = nc_def_var(ncid, "sfc_temp", NC_FLOAT, NUMDIMS,
dimids, &temp_varid)))
BAIL(res);
/* We'll store the units. */
if ((res = nc_put_att_text(ncid, temp_varid, "units",
strlen(CELSIUS), CELSIUS)))
BAIL(res);
/* We're finished defining metadata. */
if ((res = nc_enddef(ncid)))
BAIL(res);
if ((res = nc_put_var_float(ncid, temp_varid, (float *)temp)))
BAIL(res);
/* We're done! */
if ((res = nc_close(ncid)))
BAIL(res);
return 0;
}