mirror of
https://github.com/Unidata/netcdf-c.git
synced 2024-11-21 03:13:42 +08:00
92 lines
2.6 KiB
C
92 lines
2.6 KiB
C
/** \file
|
|
Write the simple_xy file, with some of the features of netCDF-4.
|
|
|
|
This is a very simple example which is based on the simple_xy example,
|
|
but whch uses netCDF-4 features, such as compression. Please see the
|
|
simple_xy example to learn more about the netCDF-3 API.
|
|
|
|
Like simple_xy_wr.c, this program writes a 2D netCDF variable (called
|
|
"data") and fills it with sample data. It has two dimensions, "x" and
|
|
"y".
|
|
|
|
Full documentation for netCDF can be found at:
|
|
http://www.unidata.ucar.edu/netcdf/docs
|
|
*/
|
|
#include <stdlib.h>
|
|
#include <stdio.h>
|
|
#include <netcdf.h>
|
|
|
|
/* This is the name of the data file we will create. */
|
|
#define FILE_NAME "simple_xy_nc4.nc"
|
|
|
|
/* We are writing 2D data, a 6 x 12 grid. */
|
|
#define NDIMS 2
|
|
#define NX 6
|
|
#define NY 12
|
|
|
|
/* Handle errors by printing an error message and exiting with a
|
|
* non-zero status. */
|
|
#define ERRCODE 2
|
|
#define ERR(e) {printf("Error: %s\n", nc_strerror(e)); exit(ERRCODE);}
|
|
|
|
int
|
|
main()
|
|
{
|
|
int ncid, x_dimid, y_dimid, varid;
|
|
int dimids[NDIMS];
|
|
size_t chunks[NDIMS];
|
|
int shuffle, deflate, deflate_level;
|
|
int data_out[NX][NY];
|
|
int x, y, retval;
|
|
|
|
/* Set chunking, shuffle, and deflate. */
|
|
shuffle = NC_SHUFFLE;
|
|
deflate = 1;
|
|
deflate_level = 1;
|
|
|
|
/* Create some pretend data. If this wasn't an example program, we
|
|
* would have some real data to write, for example, model output. */
|
|
for (x = 0; x < NX; x++)
|
|
for (y = 0; y < NY; y++)
|
|
data_out[x][y] = x * NY + y;
|
|
|
|
/* Create the file. The NC_NETCDF4 parameter tells netCDF to create
|
|
* a file in netCDF-4/HDF5 standard. */
|
|
if ((retval = nc_create(FILE_NAME, NC_NETCDF4, &ncid)))
|
|
ERR(retval);
|
|
|
|
/* Define the dimensions. */
|
|
if ((retval = nc_def_dim(ncid, "x", NX, &x_dimid)))
|
|
ERR(retval);
|
|
if ((retval = nc_def_dim(ncid, "y", NY, &y_dimid)))
|
|
ERR(retval);
|
|
|
|
/* Set up variabe data. */
|
|
dimids[0] = x_dimid;
|
|
dimids[1] = y_dimid;
|
|
chunks[0] = NX/4;
|
|
chunks[1] = NY/4;
|
|
|
|
/* Define the variable. */
|
|
if ((retval = nc_def_var(ncid, "data", NC_INT, NDIMS,
|
|
dimids, &varid)))
|
|
ERR(retval);
|
|
if ((retval = nc_def_var_chunking(ncid, varid, 0, &chunks[0])))
|
|
ERR(retval);
|
|
if ((retval = nc_def_var_deflate(ncid, varid, shuffle, deflate,
|
|
deflate_level)))
|
|
ERR(retval);
|
|
|
|
/* No need to explicitly end define mode for netCDF-4 files. Write
|
|
* the pretend data to the file. */
|
|
if ((retval = nc_put_var_int(ncid, varid, &data_out[0][0])))
|
|
ERR(retval);
|
|
|
|
/* Close the file. */
|
|
if ((retval = nc_close(ncid)))
|
|
ERR(retval);
|
|
|
|
printf("*** SUCCESS writing example file simple_xy_nc4.nc!\n");
|
|
return 0;
|
|
}
|