double L2Norm(const Mesh& mesh, const CellFilter& domain,
  const Expr& f, const QuadratureFamily& quad,
  const WatchFlag& watch)
{
  Expr I2 = Integral(domain, f*f, quad, watch);

  return sqrt(evaluateIntegral(mesh, I2));
}
double H1Norm(
  const Mesh& mesh,
  const CellFilter& filter,
  const Expr& f,
  const QuadratureFamily& quad,
  const WatchFlag& watch)
{
  Expr grad = gradient(mesh.spatialDim());
  Expr g = grad*f;
  Expr I2 = Integral(filter, f*f + g*g, quad, watch);

  return sqrt(evaluateIntegral(mesh, I2));  
}
bool DuffingFloquet()
{
  int np = MPIComm::world().getNProc();
  TEUCHOS_TEST_FOR_EXCEPT(np != 1);

  const double pi = 4.0*atan(1.0);

  /* We will do our linear algebra using Epetra */
  VectorType<double> vecType = new EpetraVectorType();

  /* Create a periodic mesh */
  int nx = 128;

  MeshType meshType = new PeriodicMeshType1D();
  MeshSource mesher = new PeriodicLineMesher(0.0, 2.0*pi, nx, meshType);
  Mesh mesh = mesher.getMesh();

  /* Create a cell filter that will identify the maximal cells
   * in the interior of the domain */
  CellFilter interior = new MaximalCellFilter();
  CellFilter pts = new DimensionalCellFilter(0);
      
  CellFilter left = pts.subset(new CoordinateValueCellPredicate(0,0.0));
  CellFilter right = pts.subset(new CoordinateValueCellPredicate(0,2.0*pi));
      
  /* Create unknown and test functions, discretized using first-order
   * Lagrange interpolants */
  Expr u1 = new UnknownFunction(new Lagrange(1), "u1");
  Expr u2 = new UnknownFunction(new Lagrange(1), "u2");
  Expr v1 = new TestFunction(new Lagrange(1), "v1");
  Expr v2 = new TestFunction(new Lagrange(1), "v2");

  /* Create differential operator and coordinate function */
  Expr dx = new Derivative(0);
  Expr x = new CoordExpr(0);

  /* We need a quadrature rule for doing the integrations */
  QuadratureFamily quad = new GaussianQuadrature(4);

  double F0 = 0.5;
  double gamma = 2.0/3.0;
  double a0 = 1.0;
  double w0 = 1.0;
  double eps = 0.5;

  Expr u1Guess = -0.75*cos(x) + 0.237*sin(x);
  Expr u2Guess = 0.237*cos(x) + 0.75*sin(x);

  DiscreteSpace discSpace(mesh, 
    List(new Lagrange(1), new Lagrange(1)),
    vecType);
  L2Projector proj(discSpace, List(u1Guess, u2Guess));
  Expr u0 = proj.project();


  Expr rhs1 = u2;
  Expr rhs2 = -w0*w0*u1 - gamma*u2 - eps*w0*w0*pow(u1,3.0)/a0/a0 
    + F0*w0*w0*sin(x);

  /* Define the weak form */
  Expr eqn = Integral(interior, 
    v1*(dx*u1 - rhs1) + v2*(dx*u2 - rhs2),
    quad);
  Expr dummyBC ; 

  NonlinearProblem prob(mesh, eqn, dummyBC, List(v1,v2), List(u1,u2), 
    u0, vecType);


  ParameterXMLFileReader reader("nox.xml");
  ParameterList solverParams = reader.getParameters();

  Out::root() << "finding periodic solution" << endl;
  NOXSolver solver(solverParams);
  prob.solve(solver);

  /* unfold the solution onto a non-periodic mesh */
      
  Expr uP = unfoldPeriodicDiscreteFunction(u0, "u_p");
  Out::root() << "uP=" << uP << endl;
      
  Mesh unfoldedMesh = DiscreteFunction::discFunc(uP)->mesh();
  DiscreteSpace unfDiscSpace = DiscreteFunction::discFunc(uP)->discreteSpace();

  FieldWriter writer = new MatlabWriter("Floquet.dat");
  writer.addMesh(unfoldedMesh);
  writer.addField("u_p[0]", new ExprFieldWrapper(uP[0]));
  writer.addField("u_p[1]", new ExprFieldWrapper(uP[1]));

  Array<Expr> a(2);
  a[0] = new Sundance::Parameter(0.0, "a1");
  a[1] = new Sundance::Parameter(0.0, "a2");


  Expr bc = EssentialBC(left, v1*(u1-uP[0]-a[0]) + v2*(u2-uP[1]-a[1]), quad);

  NonlinearProblem unfProb(unfoldedMesh, eqn, bc, 
    List(v1,v2), List(u1,u2), uP, vecType);

  unfProb.setEvalPoint(uP);

  LinearOperator<double> J = unfProb.allocateJacobian();
  Vector<double> b = J.domain().createMember();

  LinearSolver<double> linSolver
    = LinearSolverBuilder::createSolver("amesos.xml");
        
  SerialDenseMatrix<int, double> F(a.size(), a.size());

  for (int i=0; i<a.size(); i++)
  {
    Out::root() << "doing perturbed orbit #" << i << endl;
    for (int j=0; j<a.size(); j++) 
    {
      if (i==j) a[j].setParameterValue(1.0);
      else a[j].setParameterValue(0.0);
    }
        
    unfProb.computeJacobianAndFunction(J, b);
    Vector<double> w = b.copy();
    linSolver.solve(J, b, w);
    Expr w_i = new DiscreteFunction(unfDiscSpace, w);

    for (int j=0; j<a.size(); j++)
    {
      Out::root() << "postprocessing" << i << endl;

      writer.addField("w[" + Teuchos::toString(i)
        + ", " + Teuchos::toString(j) + "]", new ExprFieldWrapper(w_i[j]));
      Expr g = Integral(right, w_i[j], quad);
      F(j,i) = evaluateIntegral(unfoldedMesh, g);
    }
  }

  writer.write();

  Out::root() << "Floquet matrix = " << endl
              << F << endl;
        

  Out::root() << "doing eigenvalue analysis" << endl;
  Array<double> ew_r(a.size());
  Array<double> ew_i(a.size());
  int lWork = 6*a.size();
  Array<double> work(lWork);
  int info = 0;
  LAPACK<int, double> lapack;
  lapack.GEEV('N','N', a.size(), F.values(),
    a.size(), &(ew_r[0]), &(ew_i[0]), 0, 1, 0, 1, &(work[0]), lWork,
    &info);

  TEUCHOS_TEST_FOR_EXCEPTION(info != 0,
    std::runtime_error,
    "LAPACK GEEV returned error code =" << info);
      
  Array<double> ew(a.size());
  for (int i=0; i<a.size(); i++)
  {
    ew[i] = sqrt(ew_r[i]*ew_r[i]+ew_i[i]*ew_i[i]);
    Out::root() << setw(5) << i 
                << setw(16) << ew_r[i] 
                << setw(16) << ew_i[i] 
                << setw(16) << ew[i]
                << endl;
  }

  double err = ::fabs(ew[0] - 0.123);
  return SundanceGlobal::checkTest(err, 0.001);
}
bool BlockStochPoissonTest1D()
{
  /* We will do our linear algebra using Epetra */
  VectorType<double> vecType = new EpetraVectorType();

  /* Read a mesh */
  MeshType meshType = new BasicSimplicialMeshType();
  int nx = 32;
  MeshSource mesher = new PartitionedLineMesher(0.0, 1.0, nx, 
    meshType);
  Mesh mesh = mesher.getMesh();

  /* Create a cell filter that will identify the maximal cells
   * in the interior of the domain */
  CellFilter interior = new MaximalCellFilter();
  CellFilter pts = new DimensionalCellFilter(0);
  CellFilter left = pts.subset(new CoordinateValueCellPredicate(0,0.0));
  CellFilter right = pts.subset(new CoordinateValueCellPredicate(0,1.0));

  Expr x = new CoordExpr(0);

  /* Create the stochastic coefficients */
  int nDim = 1;
  int order = 6;
#ifdef HAVE_SUNDANCE_STOKHOS
  Out::root() << "using Stokhos hermite basis" << std::endl;
  SpectralBasis pcBasis = new Stokhos::HermiteBasis<int,double>(order);
#else
  Out::root() << "using George's hermite basis" << std::endl;
  SpectralBasis pcBasis = new HermiteSpectralBasis(nDim, order);
#endif
    
  Array<Expr> q(pcBasis.nterms());
  Array<Expr> kappa(pcBasis.nterms());
  Array<Expr> uEx(pcBasis.nterms());

  double a = 0.1;

  q[0] = -2 + pow(a,2)*(4 - 9*x)*x - 2*pow(a,3)*(-1 + x)*(1 + 3*x*(-3 + 4*x));
  q[1] = -(a*(-3 + 10*x + 2*a*(-1 + x*(8 - 9*x +
          a*(-4 + 3*(5 - 4*x)*x + 12*a*(-1 + x)*(1 + 5*(-1 + x)*x))))));
  q[2] = a*(-4 + 6*x + a*(1 - x*(2 + 3*x) + a*(4 - 28*x + 30*pow(x,2))));
  q[3] = -(pow(a,2)*(-3 + x*(20 - 21*x +
        a*(-4 + 3*(5 - 4*x)*x + 24*a*(-1 + x)*(1 + 5*(-1 + x)*x)))));
  q[4] = pow(a,3)*(1 + x*(-6 + x*(3 + 4*x)));
  q[5] = -4*pow(a,4)*(-1 + x)*x*(1 + 5*(-1 + x)*x);
  q[6] = 0.0;

  uEx[0] = -((-1 + x)*x);
  uEx[1] = -(a*(-1 + x)*pow(x,2));
  uEx[2] = a*pow(-1 + x,2)*x;
  uEx[3] = pow(a,2)*pow(-1 + x,2)*pow(x,2);
  uEx[4] = 0.0;
  uEx[5] = 0.0;
  uEx[6] = 0.0;

  kappa[0] = 1.0;
  kappa[1] = a*x;
  kappa[2] = -(pow(a,2)*(-1 + x)*x);

  kappa[3] = 1.0; // unused
  kappa[4] = 1.0; // unused
  kappa[5] = 1.0; // unused
  kappa[6] = 1.0; // unused


  Array<Expr> uBC(pcBasis.nterms());
  for (int i=0; i<pcBasis.nterms(); i++) uBC[i] = 0.0;

  int L = nDim+2;
  int P = pcBasis.nterms();
  Out::os() << "L = " << L << std::endl;
  Out::os() << "P = " << P << std::endl;
    
  /* Create the unknown and test functions. Do NOT use the spectral
   * basis here */
  Expr u = new UnknownFunction(new Lagrange(4), "u");
  Expr v = new TestFunction(new Lagrange(4), "v");

  /* Create differential operator and coordinate function */
  Expr dx = new Derivative(0);
  Expr grad = dx;


  /* We need a quadrature rule for doing the integrations */
  QuadratureFamily quad = new GaussianQuadrature(12);

  /* Now we create problem objects to build each $K_j$ and $f_j$.
   * There will be L matrix-vector pairs */
  Array<Expr> eqn(P);
  Array<Expr> bc(P);
  Array<LinearProblem> prob(P);
  Array<LinearOperator<double> > KBlock(L);
  Array<Vector<double> > fBlock(P);
  Array<Vector<double> > solnBlock;

  for (int j=0; j<P; j++)
  {
    eqn[j] = Integral(interior, kappa[j]*(grad*v)*(grad*u) + v*q[j], quad);
    bc[j] = EssentialBC(left+right, v*(u-uBC[j]), quad);
    prob[j] = LinearProblem(mesh, eqn[j], bc[j], v, u, vecType); 
    if (j<L) KBlock[j] = prob[j].getOperator();
    fBlock[j] = -1.0*prob[j].getSingleRHS();
  }

  /* Read the solver to be used on the diagonal blocks */
  LinearSolver<double> diagSolver 
    = LinearSolverBuilder::createSolver("amesos.xml");

    
  double convTol = 1.0e-12;
  int maxIters = 30;
  int verb = 1;
  StochBlockJacobiSolver solver(diagSolver, pcBasis,
    convTol, maxIters, verb);
    
  solver.solve(KBlock, fBlock, solnBlock);

  /* write the solution */
  FieldWriter w = new MatlabWriter("Stoch1D");
  w.addMesh(mesh);
  DiscreteSpace discSpace(mesh, new Lagrange(4), vecType);
  for (int i=0; i<P; i++)
  {
    L2Projector proj(discSpace, uEx[i]);
    Expr ue_i = proj.project();
    Expr df = new DiscreteFunction(discSpace, solnBlock[i]);
    w.addField("u["+ Teuchos::toString(i)+"]", 
      new ExprFieldWrapper(df));
    w.addField("uEx["+ Teuchos::toString(i)+"]", 
      new ExprFieldWrapper(ue_i));
  }
  w.write();

  double totalErr2 = 0.0;
  DiscreteSpace discSpace4(mesh, new Lagrange(4), vecType);
  for (int i=0; i<P; i++)
  {
    Expr df = new DiscreteFunction(discSpace4, solnBlock[i]);
    Expr errExpr = Integral(interior, pow(uEx[i]-df, 2.0), quad);
    Expr scaleExpr = Integral(interior, pow(uEx[i], 2.0), quad);
    double errSq = evaluateIntegral(mesh, errExpr);
    double scale = evaluateIntegral(mesh, scaleExpr);
    if (scale > 0.0) 
      Out::os() << "mode i=" << i << " error=" << sqrt(errSq/scale) << std::endl;
    else
      Out::os() << "mode i=" << i << " error=" << sqrt(errSq) << std::endl;
  }
    
  double tol = 1.0e-12;
    
  return SundanceGlobal::checkTest(sqrt(totalErr2), tol);
}
Beispiel #5
0
int main(int argc, char** argv)
{
  
  try
		{
      Sundance::init(&argc, &argv);

      /* We will do our linear algebra using Epetra */
      VectorType<double> vecType = new EpetraVectorType();

      /* Create a mesh. It will be of type BasisSimplicialMesh, and will
       * be built using a PartitionedLineMesher. */
      MeshType meshType = new BasicSimplicialMeshType();
      MeshSource mesher = new PartitionedLineMesher(0.0, 1.0, 10, meshType);
      Mesh mesh = mesher.getMesh();

      /* Create a cell filter that will identify the maximal cells
       * in the interior of the domain */
      CellFilter interior = new MaximalCellFilter();
      
      /* Create unknown and test functions, discretized using first-order
       * Lagrange interpolants */
      Expr u = new UnknownFunction(new Lagrange(1), "u");
      Expr v = new TestFunction(new Lagrange(1), "v");

      /* We need a quadrature rule for doing the integrations */
      QuadratureFamily quad = new GaussianQuadrature(2);

      
      /* Define the weak form */
      Expr eqn = Integral(interior, v*(u-1.0), quad);
      Expr bc;

      /* We can now set up the linear problem! */
      std::cerr << "setting up linear problem" << std::endl;
      LinearProblem prob(mesh, eqn, bc, v, u, vecType); 


#ifdef HAVE_CONFIG_H
      ParameterXMLFileReader reader(searchForFile("SolverParameters/bicgstab.xml"));
#else
      ParameterXMLFileReader reader("bicgstab.xml");
#endif
      ParameterList solverParams = reader.getParameters();
      std::cerr << "params = " << solverParams << std::endl;


      LinearSolver<double> solver 
        = LinearSolverBuilder::createSolver(solverParams);

      std::cerr << "solving problem" << std::endl;
      Expr soln = prob.solve(solver);

      Expr exactSoln = 1.0;

      Expr errExpr = Integral(interior, 
                              pow(soln-exactSoln, 2),
                              new GaussianQuadrature(4));

      std::cerr << "setting up norm" << std::endl;
      double errorSq = evaluateIntegral(mesh, errExpr);
      std::cerr << "error norm = " << sqrt(errorSq) << std::endl << std::endl;

      double tol = 1.0e-12;
      Sundance::passFailTest(sqrt(errorSq), tol);
    }
	catch(std::exception& e)
		{
      std::cerr << e.what() << std::endl;
		}
  Sundance::finalize(); return Sundance::testStatus(); 
}