Example #1
0
    def test_parab_subbed_Pcomps(self):

        model = Problem(impl=impl)
        root = model.root = Group()
        root.ln_solver = lin_solver()

        par = root.add('par', ParallelGroup())

        par.add('s1', MP_Point(root=2.0))
        par.add('s2', MP_Point(root=3.0))

        root.add('sumcomp', ExecComp('sum = x1+x2'))
        root.connect('par.s1.c.y', 'sumcomp.x1')
        root.connect('par.s2.c.y', 'sumcomp.x2')

        driver = model.driver = pyOptSparseDriver()
        driver.options['optimizer'] = OPTIMIZER
        driver.options['print_results'] = False
        driver.add_desvar('par.s1.p.x', lower=-100, upper=100)
        driver.add_desvar('par.s2.p.x', lower=-100, upper=100)
        driver.add_objective('sumcomp.sum')

        model.setup(check=False)
        model.run()

        if not MPI or self.comm.rank == 0:
            assert_rel_error(self, model['par.s1.p.x'], 2.0, 1.e-6)

        if not MPI or self.comm.rank == 1:
            assert_rel_error(self, model['par.s2.p.x'], 3.0, 1.e-6)
Example #2
0
    def test_parab_subbed_Pcomps(self):

        model = Problem(impl=impl)
        root = model.root = Group()
        root.ln_solver = lin_solver()

        par = root.add('par', ParallelGroup())

        par.add('s1', MP_Point(root=2.0))
        par.add('s2', MP_Point(root=3.0))

        root.add('sumcomp', ExecComp('sum = x1+x2'))
        root.connect('par.s1.c.y', 'sumcomp.x1')
        root.connect('par.s2.c.y', 'sumcomp.x2')

        driver = model.driver = pyOptSparseDriver()
        driver.add_param('par.s1.p.x', low=-100, high=100)
        driver.add_param('par.s2.p.x', low=-100, high=100)
        driver.add_objective('sumcomp.sum')

        model.setup(check=False)
        model.run()

        if not MPI or self.comm.rank == 0:
            assert_rel_error(self, model['par.s1.p.x'], 2.0, 1.e-6)

        if not MPI or self.comm.rank == 1:
            assert_rel_error(self, model['par.s2.p.x'], 3.0, 1.e-6)
Example #3
0
    def test_parab_subbed_Pcomps(self):

        model = Problem(impl=impl)
        root = model.root = Group()
        root.ln_solver = lin_solver()

        par = root.add("par", ParallelGroup())

        par.add("s1", MP_Point(root=2.0))
        par.add("s2", MP_Point(root=3.0))

        root.add("sumcomp", ExecComp("sum = x1+x2"))
        root.connect("par.s1.c.y", "sumcomp.x1")
        root.connect("par.s2.c.y", "sumcomp.x2")

        driver = model.driver = pyOptSparseDriver()
        driver.add_param("par.s1.p.x", low=-100, high=100)
        driver.add_param("par.s2.p.x", low=-100, high=100)
        driver.add_objective("sumcomp.sum")

        model.setup(check=False)
        model.run()

        if not MPI or self.comm.rank == 0:
            assert_rel_error(self, model["par.s1.p.x"], 2.0, 1.0e-6)

        if not MPI or self.comm.rank == 1:
            assert_rel_error(self, model["par.s2.p.x"], 3.0, 1.0e-6)
    def test_bounds_backtracking(self):

        class SimpleImplicitComp1(Component):
            """ A Simple Implicit Component with an additional output equation.

            f(x,z) = xz + z - 4
            y = x + 2z

            Sol: when x = 0.5, z = 2.666
            Sol: when x = 2.0, z = 1.333

            Coupled derivs:

            y = x + 8/(x+1)
            dy_dx = 1 - 8/(x+1)**2 = -2.5555555555555554

            z = 4/(x+1)
            dz_dx = -4/(x+1)**2 = -1.7777777777777777
            """

            def __init__(self):
                super(SimpleImplicitComp1, self).__init__()

                # Params
                self.add_param('x', 0.5)

                # Unknowns
                self.add_output('y', 0.0)

                # States
                self.add_state('z', 2.0, lower=1.4, upper=2.5)

                self.maxiter = 10
                self.atol = 1.0e-12

            def solve_nonlinear(self, params, unknowns, resids):
                pass

            def apply_nonlinear(self, params, unknowns, resids):
                """ Don't solve; just calculate the residual."""

                x = params['x']
                z = unknowns['z']
                resids['z'] = x*z + z - 4.0

                # Output equations need to evaluate a residual just like an explicit comp.
                resids['y'] = x + 2.0*z - unknowns['y']

            def linearize(self, params, unknowns, resids):
                """Analytical derivatives."""

                J = {}

                # Output equation
                J[('y', 'x')] = np.array([1.0])
                J[('y', 'z')] = np.array([2.0])

                # State equation
                J[('z', 'z')] = np.array([params['x'] + 1.0])
                J[('z', 'x')] = np.array([unknowns['z']])

                return J

        class SimpleImplicitComp2(Component):
            """ A Simple Implicit Component with an additional output equation.

            f(x,z) = xz + z - 4
            y = x + 2z

            Sol: when x = 0.5, z = 2.666
            Sol: when x = 2.0, z = 1.333

            Coupled derivs:

            y = x + 8/(x+1)
            dy_dx = 1 - 8/(x+1)**2 = -2.5555555555555554

            z = 4/(x+1)
            dz_dx = -4/(x+1)**2 = -1.7777777777777777
            """

            def __init__(self):
                super(SimpleImplicitComp2, self).__init__()

                # Params
                self.add_param('x', 0.5)

                # Unknowns
                self.add_output('y', 0.0)

                # States
                self.add_state('z', 2.0, lower=1.5, upper=2.5)

                self.maxiter = 10
                self.atol = 1.0e-12

            def solve_nonlinear(self, params, unknowns, resids):
                pass

            def apply_nonlinear(self, params, unknowns, resids):
                """ Don't solve; just calculate the residual."""

                x = params['x']
                z = unknowns['z']
                resids['z'] = x*z + z - 4.0

                # Output equations need to evaluate a residual just like an explicit comp.
                resids['y'] = x + 2.0*z - unknowns['y']

            def linearize(self, params, unknowns, resids):
                """Analytical derivatives."""

                J = {}

                # Output equation
                J[('y', 'x')] = np.array([1.0])
                J[('y', 'z')] = np.array([2.0])

                # State equation
                J[('z', 'z')] = np.array([params['x'] + 1.0])
                J[('z', 'x')] = np.array([unknowns['z']])

                return J

        #------------------------------------------------------
        # Test that Newton doesn't drive it past lower bounds
        #------------------------------------------------------

        top = Problem(impl=impl)
        top.root = Group()
        par = top.root.add('par', ParallelGroup())
        par.add('comp1', SimpleImplicitComp1())
        par.add('comp2', SimpleImplicitComp2())
        top.root.ln_solver = lin_solver()
        top.root.nl_solver = Newton()
        top.root.nl_solver.options['maxiter'] = 5
        top.root.add('px1', IndepVarComp('x', 1.0))
        top.root.add('px2', IndepVarComp('x', 1.0))

        # TODO: This is to get around a bug in checks. It should be fixed soon.
        par.ln_solver = lin_solver()

        top.root.connect('px1.x', 'par.comp1.x')
        top.root.connect('px2.x', 'par.comp2.x')
        top.setup(check=False)

        top['px1.x'] = 2.0
        top['px2.x'] = 2.0
        top.run()

        # Comp2 has a tighter lower bound. This test makes sure that we
        # allgathered and used the lowest alpha.

        if top.root.par.comp1.is_active():
            self.assertEqual(top['par.comp1.z'], 1.5)
        if top.root.par.comp2.is_active():
            self.assertEqual(top['par.comp2.z'], 1.5)
        J = {}
        J['obj', 'x'] = self.A
        return J


if __name__ == '__main__':
    #from openmdao.test.mpi_util import mpirun_tests
    #mpirun_tests()
    if OPT is None:
        raise unittest.SkipTest("pyoptsparse is not installed")

    if OPTIMIZER is None:
        raise unittest.SkipTest("pyoptsparse is not providing SNOPT or SLSQP")

    size = 100
    prob = Problem(impl=impl)
    root = prob.root = Group()

    root.add('p', IndepVarComp('x', val=np.ones(shape=(size, ))))
    root.add('c', LinearSolver(size=size, A=np.eye(size), b=np.arange(0,
                                                                      size)))
    root.connect('p.x', 'c.x')

    root.ln_solver = lin_solver()

    prob.setup()
    prob.run()
    err = np.sum(np.abs(prob['c.obj']))
    result = prob['p.x']
    print(result)
    print(err)