Example #1
0
def main():
    model = create_model()
    nlp = PyomoNLP(model)

    # initial guesses
    x = nlp.init_primals()
    lam = nlp.init_duals()

    nlp.set_primals(x)
    nlp.set_duals(lam)

    # NLP function evaluations
    f = nlp.evaluate_objective()
    print("Objective Function\n", f)
    df = nlp.evaluate_grad_objective()
    print("Gradient of Objective Function:\n", df)
    c = nlp.evaluate_constraints()
    print("Constraint Values:\n", c)
    c_eq = nlp.evaluate_eq_constraints()
    print("Equality Constraint Values:\n", c_eq)
    c_ineq = nlp.evaluate_ineq_constraints()
    print("Inequality Constraint Values:\n", c_ineq)
    jac = nlp.evaluate_jacobian()
    print("Jacobian of Constraints:\n", jac.toarray())
    jac_eq = nlp.evaluate_jacobian_eq()
    print("Jacobian of Equality Constraints:\n", jac_eq.toarray())
    jac_ineq = nlp.evaluate_jacobian_ineq()
    print("Jacobian of Inequality Constraints:\n", jac_ineq.toarray())
    hess_lag = nlp.evaluate_hessian_lag()
    print("Hessian of Lagrangian\n", hess_lag.toarray())
Example #2
0
def main(show_plot=True):
    if show_plot:
        import matplotlib.pylab as plt

    instance = create_problem(0.0, 10.0)
    # Discretize model using Orthogonal Collocation
    discretizer = pyo.TransformationFactory('dae.collocation')
    discretizer.apply_to(instance, nfe=100, ncp=3, scheme='LAGRANGE-RADAU')
    discretizer.reduce_collocation_points(instance,
                                          var=instance.u,
                                          ncp=1,
                                          contset=instance.t)

    # Interface pyomo model with nlp
    nlp = PyomoNLP(instance)
    x = nlp.create_new_vector('primals')
    x.fill(1.0)
    nlp.set_primals(x)

    lam = nlp.create_new_vector('duals')
    lam.fill(1.0)
    nlp.set_duals(lam)

    # Evaluate jacobian
    jac = nlp.evaluate_jacobian()
    if show_plot:
        plt.spy(jac)
        plt.title('Jacobian of the constraints\n')
        plt.show()

    # Evaluate hessian of the lagrangian
    hess_lag = nlp.evaluate_hessian_lag()
    if show_plot:
        plt.spy(hess_lag)
        plt.title('Hessian of the Lagrangian function\n')
        plt.show()

    # Build KKT matrix
    kkt = BlockMatrix(2, 2)
    kkt.set_block(0, 0, hess_lag)
    kkt.set_block(1, 0, jac)
    kkt.set_block(0, 1, jac.transpose())
    if show_plot:
        plt.spy(kkt.tocoo())
        plt.title('KKT system\n')
        plt.show()
Example #3
0
    def test_compare_evaluations(self):
        A1 = 5
        A2 = 10
        c1 = 3
        c2 = 4
        N = 6
        dt = 1

        m = create_pyomo_model(A1, A2, c1, c2, N, dt)
        solver = pyo.SolverFactory('ipopt')
        solver.options['linear_solver'] = 'mumps'
        status = solver.solve(m, tee=False)
        m_nlp = PyomoNLP(m)

        mex = create_pyomo_external_grey_box_model(A1, A2, c1, c2, N, dt)
        # mex_nlp = PyomoGreyBoxNLP(mex)
        mex_nlp = PyomoNLPWithGreyBoxBlocks(mex)

        # get the variable and constraint order and create the maps
        # reliable order independent comparisons
        m_x_order = m_nlp.primals_names()
        m_c_order = m_nlp.constraint_names()
        mex_x_order = mex_nlp.primals_names()
        mex_c_order = mex_nlp.constraint_names()

        x1list = [
            'h1[0]', 'h1[1]', 'h1[2]', 'h1[3]', 'h1[4]', 'h1[5]', 'h2[0]',
            'h2[1]', 'h2[2]', 'h2[3]', 'h2[4]', 'h2[5]', 'F1[1]', 'F1[2]',
            'F1[3]', 'F1[4]', 'F1[5]', 'F2[1]', 'F2[2]', 'F2[3]', 'F2[4]',
            'F2[5]', 'F12[0]', 'F12[1]', 'F12[2]', 'F12[3]', 'F12[4]',
            'F12[5]', 'Fo[0]', 'Fo[1]', 'Fo[2]', 'Fo[3]', 'Fo[4]', 'Fo[5]'
        ]
        x2list = [
            'egb.inputs[h1_0]', 'egb.inputs[h1_1]', 'egb.inputs[h1_2]',
            'egb.inputs[h1_3]', 'egb.inputs[h1_4]', 'egb.inputs[h1_5]',
            'egb.inputs[h2_0]', 'egb.inputs[h2_1]', 'egb.inputs[h2_2]',
            'egb.inputs[h2_3]', 'egb.inputs[h2_4]', 'egb.inputs[h2_5]',
            'egb.inputs[F1_1]', 'egb.inputs[F1_2]', 'egb.inputs[F1_3]',
            'egb.inputs[F1_4]', 'egb.inputs[F1_5]', 'egb.inputs[F2_1]',
            'egb.inputs[F2_2]', 'egb.inputs[F2_3]', 'egb.inputs[F2_4]',
            'egb.inputs[F2_5]', 'egb.outputs[F12_0]', 'egb.outputs[F12_1]',
            'egb.outputs[F12_2]', 'egb.outputs[F12_3]', 'egb.outputs[F12_4]',
            'egb.outputs[F12_5]', 'egb.outputs[Fo_0]', 'egb.outputs[Fo_1]',
            'egb.outputs[Fo_2]', 'egb.outputs[Fo_3]', 'egb.outputs[Fo_4]',
            'egb.outputs[Fo_5]'
        ]
        x1_x2_map = dict(zip(x1list, x2list))
        x1idx_x2idx_map = {
            i: mex_x_order.index(x1_x2_map[m_x_order[i]])
            for i in range(len(m_x_order))
        }

        c1list = [
            'h1bal[1]', 'h1bal[2]', 'h1bal[3]', 'h1bal[4]', 'h1bal[5]',
            'h2bal[1]', 'h2bal[2]', 'h2bal[3]', 'h2bal[4]', 'h2bal[5]',
            'F12con[0]', 'F12con[1]', 'F12con[2]', 'F12con[3]', 'F12con[4]',
            'F12con[5]', 'Focon[0]', 'Focon[1]', 'Focon[2]', 'Focon[3]',
            'Focon[4]', 'Focon[5]', 'min_inflow[1]', 'min_inflow[2]',
            'min_inflow[3]', 'min_inflow[4]', 'min_inflow[5]',
            'max_outflow[0]', 'max_outflow[1]', 'max_outflow[2]',
            'max_outflow[3]', 'max_outflow[4]', 'max_outflow[5]', 'h10', 'h20'
        ]
        c2list = [
            'egb.h1bal_1', 'egb.h1bal_2', 'egb.h1bal_3', 'egb.h1bal_4',
            'egb.h1bal_5', 'egb.h2bal_1', 'egb.h2bal_2', 'egb.h2bal_3',
            'egb.h2bal_4', 'egb.h2bal_5', 'egb.output_constraints[F12_0]',
            'egb.output_constraints[F12_1]', 'egb.output_constraints[F12_2]',
            'egb.output_constraints[F12_3]', 'egb.output_constraints[F12_4]',
            'egb.output_constraints[F12_5]', 'egb.output_constraints[Fo_0]',
            'egb.output_constraints[Fo_1]', 'egb.output_constraints[Fo_2]',
            'egb.output_constraints[Fo_3]', 'egb.output_constraints[Fo_4]',
            'egb.output_constraints[Fo_5]', 'min_inflow[1]', 'min_inflow[2]',
            'min_inflow[3]', 'min_inflow[4]', 'min_inflow[5]',
            'max_outflow[0]', 'max_outflow[1]', 'max_outflow[2]',
            'max_outflow[3]', 'max_outflow[4]', 'max_outflow[5]', 'h10', 'h20'
        ]
        c1_c2_map = dict(zip(c1list, c2list))
        c1idx_c2idx_map = {
            i: mex_c_order.index(c1_c2_map[m_c_order[i]])
            for i in range(len(m_c_order))
        }

        # get the primals from m and put them in the correct order for mex
        m_x = m_nlp.get_primals()
        mex_x = np.zeros(len(m_x))
        for i in range(len(m_x)):
            mex_x[x1idx_x2idx_map[i]] = m_x[i]

        # get the duals from m and put them in the correct order for mex
        m_lam = m_nlp.get_duals()
        mex_lam = np.zeros(len(m_lam))
        for i in range(len(m_x)):
            mex_lam[c1idx_c2idx_map[i]] = m_lam[i]

        mex_nlp.set_primals(mex_x)
        mex_nlp.set_duals(mex_lam)

        m_obj = m_nlp.evaluate_objective()
        mex_obj = mex_nlp.evaluate_objective()
        self.assertAlmostEqual(m_obj, mex_obj, places=4)

        m_gobj = m_nlp.evaluate_grad_objective()
        mex_gobj = mex_nlp.evaluate_grad_objective()
        check_vectors_specific_order(self, m_gobj, m_x_order, mex_gobj,
                                     mex_x_order, x1_x2_map)

        m_c = m_nlp.evaluate_constraints()
        mex_c = mex_nlp.evaluate_constraints()
        check_vectors_specific_order(self, m_c, m_c_order, mex_c, mex_c_order,
                                     c1_c2_map)

        m_j = m_nlp.evaluate_jacobian()
        mex_j = mex_nlp.evaluate_jacobian().todense()
        check_sparse_matrix_specific_order(self, m_j, m_c_order, m_x_order,
                                           mex_j, mex_c_order, mex_x_order,
                                           c1_c2_map, x1_x2_map)

        m_h = m_nlp.evaluate_hessian_lag()
        mex_h = mex_nlp.evaluate_hessian_lag()
        check_sparse_matrix_specific_order(self, m_h, m_x_order, m_x_order,
                                           mex_h, mex_x_order, mex_x_order,
                                           x1_x2_map, x1_x2_map)

        mex_h = 0 * mex_h
        mex_nlp.evaluate_hessian_lag(out=mex_h)
        check_sparse_matrix_specific_order(self, m_h, m_x_order, m_x_order,
                                           mex_h, mex_x_order, mex_x_order,
                                           x1_x2_map, x1_x2_map)
Example #4
0

#################################################################
m = create_model(4.5, 1.0)
opt = pyo.SolverFactory('ipopt')
results = opt.solve(m, tee=True)

#################################################################
nlp = PyomoNLP(m)
x = nlp.init_primals()
y = compute_init_lam(nlp, x=x)
nlp.set_primals(x)
nlp.set_duals(y)

J = nlp.evaluate_jacobian()
H = nlp.evaluate_hessian_lag()

M = BlockSymMatrix(2)
M[0, 0] = H
M[1, 0] = J

Np = BlockMatrix(2, 1)
Np[0, 0] = nlp.extract_submatrix_hessian_lag(
    pyomo_variables_rows=nlp.get_pyomo_variables(),
    pyomo_variables_cols=[m.eta1, m.eta2])
Np[1, 0] = nlp.extract_submatrix_jacobian(
    pyomo_variables=[m.eta1, m.eta2],
    pyomo_constraints=nlp.get_pyomo_constraints())

ds = spsolve(M.tocsc(), Np.tocsc())
print(nlp.variable_names())