Dear Firedrakers, For the model, https://github.com/booker213/compressible_acoustic/blob/master/Firedrake/1D/... I'm interested in finding out how the energy in my system is distributed at the end of my model. My naive approach, below, was to try and create a function, so I could visualise it. localenergyfile = File('./Results/local_energy.pvd') E_local = Function(R, name="Local Energy") E_local = 0.5*(inner(u,u) + rho**2 localenergyfile.write(E_local , time =t) But this does not work. How would I go about implementing this? Regards, Will