computeHeatFlux

Hi all,
From the dev guide I would like to use the computeHeatFlux on an adLattice-D2Q5 lattice to find the actual heat flux. I am including that in the VTK file.

[size=x-small][i]void writeVTK(MultiBlockLattice2D<T,ADESCRIPTOR>& adLattice,
RayleighBenardFlowParam<T,NSDESCRIPTOR,ADESCRIPTOR> const& parameters, plint iT)
{
T dx = parameters.getDeltaX();
T dt = parameters.getDeltaT();

VtkImageOutput2D<T> vtkOut(createFileName("vtk", iT, 6), dx);
// Temperature is the order-0 moment of the advection-diffusion model. It can
//    therefore be computed with the function "computeDensity".
vtkOut.writeData<float>(*computeDensity(adLattice), "temperature", (T)1);
vtkOut.writeData<2,float>(*computeHeatFlux(adLattice.getBoundingBox(),adLattice), "HeatFlux", (T)1);

}[/i][/size]

Trouble is…I am getting a scope declaration error.

Can anyone help me on that. Do I need to include a separate header file on that or is it that it just wont work with the given lattice