From: Roy Stogner <roy@st...>  20080903 20:53:03

On Wed, 3 Sep 2008, yunfei zhu wrote: > I am following example 13 and trying to solve a set of nonlinear PDEs using > the solver of libmesh. > I have noted that: >> From previous Newton iterate, the variable values of "u" and "v" can be > assigned by > u += phi[l][qp]*navier_stokes_system.current_solution (dof_indices_u[l]); > v += phi[l][qp]*navier_stokes_system.current_solution (dof_indices_v[l]); > For the first nonlinear loop, > "current_solution (dof_indices_u[l])" is zero, so all the initial values of > "u" and "v" are assigned 0. But I would like to give the variables nonzero > initial values, could you guys please tell me how should I do that? what > function should be used? Thanks in advance. It depends how your initial values are defined. If they're a known function of (x,y,z), then try System::project_solution.  Roy 