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Tempus_UnitTest_ERK_ForwardEuler.cpp
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1 // @HEADER
2 // ****************************************************************************
3 // Tempus: Copyright (2017) Sandia Corporation
4 //
5 // Distributed under BSD 3-clause license (See accompanying file Copyright.txt)
6 // ****************************************************************************
7 // @HEADER
8 
10 
11 #include "../TestModels/DahlquistTestModel.hpp"
12 
13 
14 namespace Tempus_Unit_Test {
15 
16 using Teuchos::RCP;
17 using Teuchos::rcp;
18 using Teuchos::rcp_const_cast;
19 using Teuchos::rcp_dynamic_cast;
20 
21 
22 // ************************************************************
23 // ************************************************************
24 TEUCHOS_UNIT_TEST(ERK_ForwardEuler, Default_Construction)
25 {
26  auto stepper = rcp(new Tempus::StepperERK_ForwardEuler<double>());
28 
29  // Test stepper properties.
30  TEUCHOS_ASSERT(stepper->getOrder() == 1);
31  const auto rk_fe = stepper->getTableau();
32 
33  TEUCHOS_ASSERT( rk_fe->isTVD() );
34  TEUCHOS_ASSERT( rk_fe->getTVDCoeff() == 1 );
35 }
36 
37 
38 // ************************************************************
39 // ************************************************************
40 TEUCHOS_UNIT_TEST(ERK_ForwardEuler, StepperFactory_Construction)
41 {
42  auto model = rcp(new Tempus_Test::SinCosModel<double>());
43  testFactoryConstruction("RK Forward Euler", model);
44 }
45 
46 
47 // ************************************************************
48 // ************************************************************
49 TEUCHOS_UNIT_TEST(ERK_ForwardEuler, AppAction)
50 {
51  auto stepper = rcp(new Tempus::StepperERK_ForwardEuler<double>());
52  auto model = rcp(new Tempus_Test::SinCosModel<double>());
53  testRKAppAction(stepper, model, out, success);
54 }
55 
56 
57 // ************************************************************
58 // ************************************************************
59 TEUCHOS_UNIT_TEST(ERK_ForwardEuler, FSAL)
60 {
61  auto stepper = rcp(new Tempus::StepperERK_ForwardEuler<double>());
63  model = rcp(new Tempus_Test::DahlquistTestModel<double>(-1.0, true));
64 
65  stepper->setModel(model);
66  stepper->setICConsistency("Consistent");
67  stepper->setUseFSAL(true);
68  stepper->initialize();
69 
70  // Create a SolutionHistory.
71  auto solutionHistory = Tempus::createSolutionHistoryME(model);
72 
73  // Take one time step.
74  stepper->setInitialConditions(solutionHistory);
75  solutionHistory->initWorkingState();
76  double dt = 1.0;
77  solutionHistory->getWorkingState()->setTimeStep(dt);
78  solutionHistory->getWorkingState()->setTime(dt);
79  stepper->takeStep(solutionHistory);
80 
81  // Test solution.
82  const double relTol = 1.0e-14;
83 
84  // ICs
85  auto currentState = solutionHistory->getCurrentState();
86  const double x_0 = get_ele(*(currentState->getX()), 0);
87  const double xDot_0 = get_ele(*(currentState->getXDot()), 0);
88  TEST_FLOATING_EQUALITY(x_0, 1.0, relTol);
89  TEST_FLOATING_EQUALITY(xDot_0, -1.0, relTol);
90  TEST_ASSERT(std::abs(currentState->getTime()) < relTol);
91 
92  // After one step.
93  auto workingState = solutionHistory->getWorkingState();
94  const double x_1 = get_ele(*(workingState->getX()), 0);
95  const double xDot_1 = get_ele(*(workingState->getXDot()), 0);
96  //out << "xDot_1 = " << xDot_1 << std::endl;
97  TEST_ASSERT(std::abs(x_1 ) < relTol);
98  TEST_ASSERT(std::abs(xDot_1) < relTol);
99  TEST_FLOATING_EQUALITY(workingState->getTime(), 1.0, relTol);
100 
101 }
102 
103 
104 } // namespace Tempus_Unit_Test
void testRKAppAction(const Teuchos::RCP< Tempus::StepperRKBase< double > > &stepper, const Teuchos::RCP< const Thyra::ModelEvaluator< double > > &model, Teuchos::FancyOStream &out, bool &success)
Unit test utility for Stepper RK AppAction.
void testExplicitRKAccessorsFullConstruction(const RCP< Tempus::StepperExplicitRK< double > > &stepper)
Unit test utility for ExplicitRK Stepper construction and accessors.
void testFactoryConstruction(std::string stepperType, const Teuchos::RCP< const Thyra::ModelEvaluator< double > > &model)
Unit test utility for Stepper construction through StepperFactory.
The classic Dahlquist Test Problem.
#define TEST_FLOATING_EQUALITY(v1, v2, tol)
#define TEST_ASSERT(v1)
Sine-Cosine model problem from Rythmos. This is a canonical Sine-Cosine differential equation with a...
Teuchos::RCP< SolutionHistory< Scalar > > createSolutionHistoryME(const Teuchos::RCP< const Thyra::ModelEvaluator< Scalar > > &model)
Nonmember contructor from a Thyra ModelEvaluator.
TEUCHOS_DEPRECATED RCP< T > rcp(T *p, Dealloc_T dealloc, bool owns_mem)
TEUCHOS_UNIT_TEST(BackwardEuler, Default_Construction)
Forward Euler Runge-Kutta Butcher Tableau.
#define TEUCHOS_ASSERT(assertion_test)