
Lagrangian1D::Lagrangian1D(bool rigid_walls):
  rigid_walls_(rigid_walls) {}

double Lagrangian1D::CalcVelocity
(int i, vector<double> const& /*vp*/,
 vector<Primitive> const& hv) const
{
  if(i==0){
    if(rigid_walls_)
      return 0;
    else