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#include <string.h>
#include "netcdf.hh"
#define NUM(array) (sizeof(array)/sizeof(array[0]))
int
main( void )
{
const char* path = "example.nc";
NcNewFile nc (path, NcFile::Clobber); // Create and leave in define mode
// Check if the file was opened
if (! nc.is_valid()) {
cerr << "can't create netCDF file " << path << "\n";
return;
}
// Create dimensions
NcDim* latd = nc.add_dim("lat", 4);
NcDim* lond = nc.add_dim("lon", 3);
NcDim* frtimed = nc.add_dim("frtime");
NcDim* timelend = nc.add_dim("timelen",20);
// Create variables and their attributes
NcVar* P = nc.add_var("P", ncFloat, frtimed, latd, lond);
P->add_att("long_name", "pressure at maximum wind");
P->add_att("units", "hectopascals");
static float range[] = {0., 1500.};
P->add_att("valid_range", NUM(range), range);
P->add_att("_FillValue", -9999.0f);
NcVar* lat = nc.add_var("lat", ncFloat, latd);
lat->add_att("long_name", "latitude");
lat->add_att("units", "degrees_north");
NcVar* lon = nc.add_var("lon", ncFloat, lond);
lon->add_att("long_name", "longitude");
lon->add_att("units", "degrees_east");
NcVar* frtime = nc.add_var("frtime", ncLong, frtimed);
frtime->add_att("long_name", "forecast time");
frtime->add_att("units", "hours");
NcVar* reftime = nc.add_var("reftime",ncChar,timelend);
reftime->add_att("long_name", "reference time");
reftime->add_att("units", "text_time");
NcVar* scalar = nc.add_var("scalarv",ncLong);
scalar->add_att("scalar_att", 1.0);
// Global attributes
nc.add_att("history", "created by Unidata LDM from NPS broadcast");
nc.add_att("title", "NMC Global Product Set: Pressure at Maximum Wind");
// Start writing data, implictly leaves define mode
float *lats = new float[latd->size()];
for(int i = 0; i < latd->size(); i++)
lats[i] = -90. + 2.5*i;
lat->put(lats, latd->size());
float *lons = new float[lond->size()];
for(i = 0; i < lond->size(); i++)
lons[i] = -180. + 5.*i;
lon->put(lons, lond->size());
static long frtimes[] = {12, 18};
frtime->put(frtimes, NUM(frtimes));
static char* s = "1992 03 04 12:00" ;
reftime->put(s, strlen(s));
static float P_data[] = {
950, 951, 952, 953, 954, 955, 956, 957, 958, 959, 960, 961,
962, 963, 964, 965, 966, 967, 968, 969, 970, 971, 972, 973
};
P->put(P_data, P->edges());
// close of nc takes place in destructor
}
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