On 25 May 2011 23:16, Douglas Brinkerhoff <[email protected]> wrote: > New question #159021 on DOLFIN: > https://answers.launchpad.net/dolfin/+question/159021 > > I would like to assign an initial guess to two solution variables in the > following way, given two functions u0 and v0: > > > V = FunctionSpace(mesh,"Lagrange",1) > W = MixedFunctionSpace([V,V]) > > phi,psi = TestFunctions(W) > dU = TrialFunctions(W) > U = Function(W) > > du,dv = split(dU) > u,v = split(U) > > #Here is where I would like to assign initial values u0 and v0 for my > non-linear problem > u.assign(u0) > v.assign(v0) > > u0 and v0 are already defined as functions on the appropriate function space. > > When I use this particular syntax, I receive an error message stating that > indexed objects don't have an assign method. Fair enough, but how do I > bypass this so that I can assign an initial guess. This problem cannot > converge from a zero starting solution. >
You could also project u0,v0 into u,v: a = (du*phi + dv*psi)*dx L = (u0*phi + v0*psi)*dx problem = VariationalProblem(a, L) problem.solve(U) Not tested! But it would be nice with a more direct way to assign to a subfunction. Martin _______________________________________________ Mailing list: https://launchpad.net/~dolfin Post to : [email protected] Unsubscribe : https://launchpad.net/~dolfin More help : https://help.launchpad.net/ListHelp
