def eqn(self): t = self.u.grid.stepping_dim return iso_stencil(self.u, self.m, t.spacing, self.damp, self.kernel)
def eqn(self, m, damp, u, kernel): t = u.grid.stepping_dim return iso_stencil(u, m, t.spacing, damp, kernel)
def eqn(self, m, damp, u, time_order): t = u.grid.stepping_dim return iso_stencil(u, time_order, m, t.spacing, damp)