def METHOD_NAME(self, model, positions, q, dofs,
                        ni, o1, e1, f1):
    n = self.n
    du_axial = zeros(n, 'float64')
    for i in range(self.n):
        n0, n1 = self.node_ids[i, :]
        n11 = dofs[(n0, 1)]
        n21 = dofs[(n1, 1)]
        q_axial = array([
            q[n11],
            q[n21],
        ])
        u_axial = q_axial
        du_axial[i] = u_axial[0] - u_axial[1]
    s = self.s
    bi = self.B
    e1[ni : ni+n] = du_axial * s
    f1[ni : ni+n] = bi * du_axial
    o1[ni : ni+n] = f1[ni: ni+n] * s
    #return (axial_strain, axial_stress, axial_force)