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#include <stdio.h>
#include "cdi.h"
#define nlon 12 // Number of longitudes
#define nlat 6 // Number of latitudes
#define nhlev 6 // Number of half hybrid levels
#define nflev 5 // Number of full hybrid levels
#define nts 3 // Number of time steps
int
main(void)
{
int gridID, zaxisID1, zaxisID2, zaxisID3, zaxisID4, taxisID;
int vlistID, varID1, varID2, varID3, varID4, streamID;
SizeType numMissVals = 0;
double lons[nlon] = { 0, 30, 60, 90, 120, 150, 180, 210, 240, 270, 300, 330 };
double lats[nlat] = { -75, -45, -15, 15, 45, 75 };
double levs[nhlev] = { 1, 2, 3, 4, 5, 6 };
double levs2[nhlev] = { 2, 3, 4, 5, 6, -1 };
double vct[2 * nhlev] = { 0, 6000, 10000, 16000, 8000, 0, 0, 0.0004, 0.03, 0.2, 0.7, 1.0 };
double var1[nlon * nlat];
double var2[nlon * nlat * nflev];
double var3[nlon * nlat * nhlev];
double var4[nlon * nlat * nflev];
// Create a regular lon/lat grid
gridID = gridCreate(GRID_LONLAT, nlon * nlat);
gridDefXsize(gridID, nlon);
gridDefYsize(gridID, nlat);
gridDefXvals(gridID, lons);
gridDefYvals(gridID, lats);
// Create a surface level Z-axis
zaxisID1 = zaxisCreate(ZAXIS_SURFACE, 1);
// Create a hybrid level Z-axis
zaxisID2 = zaxisCreate(ZAXIS_HYBRID, nflev);
zaxisDefLevels(zaxisID2, levs);
zaxisDefVct(zaxisID2, nhlev * 2, vct);
// Create a hybrid half level Z-axis
zaxisID3 = zaxisCreate(ZAXIS_HYBRID, nhlev);
zaxisDefLevels(zaxisID3, levs);
zaxisDefVct(zaxisID3, nhlev * 2, vct);
// Create a hybrid level Z-axis
zaxisID4 = zaxisCreate(ZAXIS_HYBRID, nflev);
zaxisDefLevels(zaxisID4, levs);
zaxisDefLbounds(zaxisID4, levs);
zaxisDefUbounds(zaxisID4, levs2);
zaxisDefVct(zaxisID4, nhlev * 2, vct);
// Create a variable list
vlistID = vlistCreate();
// Define the variables
varID1 = vlistDefVar(vlistID, gridID, zaxisID1, TIME_VARYING);
varID2 = vlistDefVar(vlistID, gridID, zaxisID2, TIME_VARYING);
varID3 = vlistDefVar(vlistID, gridID, zaxisID3, TIME_VARYING);
varID4 = vlistDefVar(vlistID, gridID, zaxisID4, TIME_VARYING);
// Define the variable names
vlistDefVarName(vlistID, varID1, "sp");
vlistDefVarName(vlistID, varID2, "t");
vlistDefVarName(vlistID, varID3, "w");
vlistDefVarName(vlistID, varID4, "u");
// Create a Time axis
taxisID = taxisCreate(TAXIS_ABSOLUTE);
// Assign the Time axis to the variable list
vlistDefTaxis(vlistID, taxisID);
// Create a dataset in netCDF format
streamID = streamOpenWrite("example.nc", CDI_FILETYPE_NC);
if (streamID < 0)
{
fprintf(stderr, "%s\n", cdiStringError(streamID));
return (1);
}
// Assign the variable list to the dataset
streamDefVlist(streamID, vlistID);
// Loop over the number of time steps
for (int tsID = 0; tsID < nts; tsID++)
{
// Set the verification date to 1985-01-01 + tsID
taxisDefVdate(taxisID, 19850101 + tsID);
// Set the verification time to 12:00:00
taxisDefVtime(taxisID, 120000);
// Define the time step
streamDefTimestep(streamID, tsID);
// Init var1 and var2
for (size_t i = 0; i < nlon * nlat; ++i) var1[i] = 1.1;
for (size_t k = 0; k < nflev; ++k)
for (size_t i = 0; i < nlon * nlat; ++i) var2[i + k * nlon * nlat] = 2.2 + (double) k;
for (size_t k = 0; k < nhlev; ++k)
for (size_t i = 0; i < nlon * nlat; ++i) var3[i + k * nlon * nlat] = -2.2 - (double) k;
for (size_t k = 0; k < nflev; ++k)
for (size_t i = 0; i < nlon * nlat; ++i) var4[i + k * nlon * nlat] = 100.0 + (double) k;
// Write var1 and var2
streamWriteVar(streamID, varID1, var1, numMissVals);
streamWriteVar(streamID, varID2, var2, numMissVals);
streamWriteVar(streamID, varID3, var3, numMissVals);
streamWriteVar(streamID, varID4, var4, numMissVals);
}
// Close the output stream
streamClose(streamID);
// Destroy the objects
vlistDestroy(vlistID);
taxisDestroy(taxisID);
zaxisDestroy(zaxisID1);
zaxisDestroy(zaxisID2);
gridDestroy(gridID);
return 0;
}
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