Dear all, Hopefully this will help provide a bit more context for the problem. Will ________________________________ From: firedrake-bounces@imperial.ac.uk <firedrake-bounces@imperial.ac.uk> on behalf of David Ham <David.Ham@imperial.ac.uk> Sent: 18 February 2016 10:21 To: firedrake Subject: Re: [firedrake] Restricting a test function space Hi Will, Can you provide a bit more context as to what you are attempting to do? It is indeed the case that Dirichlet boundary conditions restrict the test space in that sense (this is often referred to as "lifting" the boundary conditions). However it's not generally possible to lift the component of a vector field normal to the boundary (because this does not directly correspond to a particular set of degrees of freedom), so if you can provide a little more context about the problem, we may be able to provide a suitable alternative. Regards, David On Wed, 17 Feb 2016 at 19:50 William Booker <scwb@leeds.ac.uk<mailto:scwb@leeds.ac.uk>> wrote: Dear all, If I wanted to restrict a test function space, say $\underline{\Phi} . \underline{n}$ = 0 , would that be covered by including a dirichlet boundary condition for the test function in the solver options? Regards Will