//
// code snippet for wrfvdfcreate. 
//
{

	VDC vdc(VDC::NETCDF4);

	// Open the VDC master file for writing. Have to specify how
	// many compression ratios we will have
	//
	status = vdc.Initialize(masterpath, "w");

	// Set up compression parameters. We will use the same ones for all
	// variables. Ditto for boundary periodicity
	//
	vdc.SetCompressionBlock(opt.bs, opt.wname, opt.wmode, opt.cratios());
	vdc.SetPeriodicBoundary(opt.periodic);

	// All 3D variables have the same dimensions, named "x", "y", 
	// and "z", plus time, "t"
	//
	vector <string> dimnames;
	dimnames.push_back("x");
	dimnames.push_back("y");
	dimnames.push_back("z");
	dimnames.push_back("t");

    // Dimension lenths.
    //
    vector <size_t> dimlens;
    dimlens.push_back(wrf.dims[0]);
    dimlens.push_back(wrf.dims[1]);
    dimlens.push_back(wrf.dims[2]);
    dimlens.push_back(wrf.numts);

	// Identify the axis for each dimension
	//
	vector <enum> axes;
	axes.push_back(VDC:X);
	axes.push_back(VDC:Y);
	axes.push_back(VDC:Z);
	axes.push_back(VDC:T);

    // Each dimension in the VDC has a 1D coordinate variable of the same
    // name. We also need to define the multi-dimensional, time varying
	// "ELEVATION" coordinate variable.
	//
	vector <string> coordnames;
	coordnames.push_back(dimnames[0]);
	coordnames.push_back(dimnames[1]);
	coordnames.push_back("ELEVATION");	
	coordnames.push_back(dimnames[3]);

    // Define dimensions and 1D coordinate variable associated with the
    // dimension. The DefineDimension() method both defines a dimension
    // name and length, as well as a 1D coordinate variable, of the same
    // name, with uniform sampling.
    //
    // Here we only have 4: x, y, z, and time (t)
    //
    for (int i=0; i<dimnames.size(); i++) {
        vdc.DefineDimension(dimnames[i], dimlens[i], axes[i]);
    }

	// Re-Define the X, Y, and T CF 1D coordinate variables. These have already
	// been implicity defined by DefineDimension(), but we need to provide
	// units. Also  need to define a ELEVATION coordinate variable.
	// Need to use the more
	// general DefineCoordVar for elevation and time coordinate variable
	// because elevation is multi-dimensional, and time is non-uniform.
	//
	vdc.DefineCoordVarUniform(
		coordnames[0], dimnames[0], "meters", axes[0], VDC::FLOAT32, false
	);
	vdc.DefineCoordVarUniform(
		coordnames[1], dimnames[1], "meters", axes[1], VDC::FLOAT32, false
	);


	// Now define ELEVATION coordinate variable, which is a function of 
	// x, y, and t. Also, it is compressed.
	//
	vector <string> ele_dim_names;
	ele_dim_names.push_back(dim_names[0]);
	ele_dim_names.push_back(dim_names[1]);
	ele_dim_names.push_back(dim_names[3]);
	vdc.DefineCoordVar(
		coordnames[2], ele_dim_names, "meters", axes[2], VDC::FLOAT32, true
	);

	// Finally define time coordinate variable, which in general has non
	// uniform sampling
	//
	vector <string> time_dim_names;
	time_dim_names.push_back(dim_names[3]);
	vdc.DefineCoordVar(
		coordnames[3], time_dim_names, "seconds", axes[3], VDC::FLOAT32, false
	);

	// Now define each of the 3D variables. We would need to do similar
	// thing for each 2D variable...
	// Again not units, but this time the variables are compressed
	//
	for (int i=0; i<wrf.vars3d.size(); i++) {
		DefineDataVar(
			wrf.vars3d[i], dimnames, coordnames, "", VDC::FLOAT32, true
		);
	}

	// We're done defining the master file
	//
	vdc.EndDefine();

	// Go ahead and calculate and write out the time-invariant 
	// spatial coordinate variables, and the time coordinate variable 
	//
	// We'll not write out the ELEVATION variable until we populate the VDC
	//
	size_t nx = dimlens[0];
	float deltax = (wrf.extents[3] - wrf.extents[0]) / (nx-1);
	for (int i=0; i<nx; i++) {
		xcoords[i] = wrf.extents[0] + i * deltax;
	}

	size_t ny = dimlens[1];
	float deltay = (wrf.extents[4] - wrf.extents[1]) / (ny-1);
	for (int i=0; i<ny; i++) {
		ycoords[i] = wrf.extents[1] + i * deltay;
	}

	size_t nt = dimlens[2];
	for (int i=0; i<nt; i++) {
		tcoords[i] = wrf.times[i];
	}


	// Now we write the time-invariant coordinate variables
	// using the simple "PutVar" method
	//
	vdc.PutVar(coordnames[0], xcoords);
	vdc.PutVar(coordnames[1], ycoords);
//	vdc.PutVar(coordnames[2], zcoords);
	vdc.PutVar(coordnames[3], tcoords);
	
}