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#ifndef ASSEMBLER_FINITE_DIFFERENCE_CHECK
#define ASSEMBLER_FINITE_DIFFERENCE_CHECK
#define ABORT_ON_ERROR
void infinitesimalVariation(Configuration& c, double eps, int i)
{
if (i<3)
c.r[i] += eps;
else
c.q = c.q.mult(Rotation<3,double>::exp((i==3)*eps,
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(i==4)*eps,
(i==5)*eps));
}
template <class GridType>
void strainFD(const std::vector<Configuration>& x,
double pos,
Dune::array<Dune::FieldMatrix<double,2,6>, 6>& fdStrainDerivatives,
const RodAssembler<GridType>& assembler)
{
assert(x.size()==2);
double eps = 1e-8;
typename GridType::template Codim<0>::EntityPointer element = assembler.grid_->template leafbegin<0>();
// ///////////////////////////////////////////////////////////
// Compute gradient by finite-difference approximation
// ///////////////////////////////////////////////////////////
std::vector<Configuration> forwardSolution = x;
std::vector<Configuration> backwardSolution = x;
for (size_t i=0; i<x.size(); i++) {
Dune::FieldVector<double,6> fdGradient;
for (int j=0; j<6; j++) {
infinitesimalVariation(forwardSolution[i], eps, j);
infinitesimalVariation(backwardSolution[i], -eps, j);
// fdGradient[j] = (assembler.computeEnergy(forwardSolution) - assembler.computeEnergy(backwardSolution))
// / (2*eps);
Dune::FieldVector<double,6> strain;
strain = assembler.getStrain(forwardSolution, element, pos);
strain -= assembler.getStrain(backwardSolution, element, pos);
strain /= 2*eps;
for (int m=0; m<6; m++)
fdStrainDerivatives[m][i][j] = strain[m];
forwardSolution[i] = x[i];
backwardSolution[i] = x[i];
}
}
}
template <class GridType>
void strain2ndOrderFD(const std::vector<Configuration>& x,
double pos,
Dune::array<Dune::Matrix<Dune::FieldMatrix<double,6,6> >, 3>& translationDer,
Dune::array<Dune::Matrix<Dune::FieldMatrix<double,3,3> >, 3>& rotationDer,
const RodAssembler<GridType>& assembler)
{
assert(x.size()==2);
double eps = 1e-3;
typename GridType::template Codim<0>::EntityPointer element = assembler.grid_->template leafbegin<0>();
for (int m=0; m<3; m++) {
translationDer[m].setSize(2,2);
translationDer[m] = 0;
rotationDer[m].setSize(2,2);
rotationDer[m] = 0;
}
// ///////////////////////////////////////////////////////////
// Compute gradient by finite-difference approximation
// ///////////////////////////////////////////////////////////
std::vector<Configuration> forwardSolution = x;
std::vector<Configuration> backwardSolution = x;
std::vector<Configuration> forwardForwardSolution = x;
std::vector<Configuration> forwardBackwardSolution = x;
std::vector<Configuration> backwardForwardSolution = x;
std::vector<Configuration> backwardBackwardSolution = x;
for (int i=0; i<2; i++) {
for (int j=0; j<3; j++) {
for (int k=0; k<2; k++) {
for (int l=0; l<3; l++) {
if (i==k && j==l) {
infinitesimalVariation(forwardSolution[i], eps, j+3);
infinitesimalVariation(backwardSolution[i], -eps, j+3);
// Second derivative
// fdHessian[j][k] = (assembler.computeEnergy(forwardSolution)
// - 2*assembler.computeEnergy(x)
// + assembler.computeEnergy(backwardSolution)) / (eps*eps);
Dune::FieldVector<double,6> strain;
strain = assembler.getStrain(forwardSolution, element, pos);
strain += assembler.getStrain(backwardSolution, element, pos);
strain.axpy(-2, assembler.getStrain(x, element, pos));
strain /= eps*eps;
for (int m=0; m<3; m++)
rotationDer[m][i][k][j][l] = strain[3+m];
forwardSolution = x;
backwardSolution = x;
} else {
infinitesimalVariation(forwardForwardSolution[i], eps, j+3);
infinitesimalVariation(forwardForwardSolution[k], eps, l+3);
infinitesimalVariation(forwardBackwardSolution[i], eps, j+3);
infinitesimalVariation(forwardBackwardSolution[k], -eps, l+3);
infinitesimalVariation(backwardForwardSolution[i], -eps, j+3);
infinitesimalVariation(backwardForwardSolution[k], eps, l+3);
infinitesimalVariation(backwardBackwardSolution[i],-eps, j+3);
infinitesimalVariation(backwardBackwardSolution[k],-eps, l+3);
// fdHessian[j][k] = (assembler.computeEnergy(forwardForwardSolution)
// + assembler.computeEnergy(backwardBackwardSolution)
// - assembler.computeEnergy(forwardBackwardSolution)
// - assembler.computeEnergy(backwardForwardSolution)) / (4*eps*eps);
Dune::FieldVector<double,6> strain;
strain = assembler.getStrain(forwardForwardSolution, element, pos);
strain += assembler.getStrain(backwardBackwardSolution, element, pos);
strain -= assembler.getStrain(forwardBackwardSolution, element, pos);
strain -= assembler.getStrain(backwardForwardSolution, element, pos);
strain /= 4*eps*eps;
for (int m=0; m<3; m++)
rotationDer[m][i][k][j][l] = strain[3+m];
forwardForwardSolution = x;
forwardBackwardSolution = x;
backwardForwardSolution = x;
backwardBackwardSolution = x;
}
}
}
}
}
}
template <class GridType>
void strain2ndOrderFD2(const std::vector<Configuration>& x,
double pos,
Dune::FieldVector<double,1> shapeGrad[2],
Dune::FieldVector<double,1> shapeFunction[2],
Dune::array<Dune::Matrix<Dune::FieldMatrix<double,6,6> >, 3>& translationDer,
Dune::array<Dune::Matrix<Dune::FieldMatrix<double,3,3> >, 3>& rotationDer,
const RodAssembler<GridType>& assembler)
{
assert(x.size()==2);
double eps = 1e-3;
for (int m=0; m<3; m++) {
translationDer[m].setSize(2,2);
translationDer[m] = 0;
rotationDer[m].setSize(2,2);
rotationDer[m] = 0;
}
// ///////////////////////////////////////////////////////////
// Compute gradient by finite-difference approximation
// ///////////////////////////////////////////////////////////
std::vector<Configuration> forwardSolution = x;
std::vector<Configuration> backwardSolution = x;
for (int k=0; k<2; k++) {
for (int l=0; l<3; l++) {
infinitesimalVariation(forwardSolution[k], eps, l+3);
infinitesimalVariation(backwardSolution[k], -eps, l+3);
Dune::array<Dune::FieldMatrix<double,2,6>, 6> forwardStrainDer;
assembler.strainDerivative(forwardSolution, pos, shapeGrad, shapeFunction, forwardStrainDer);
Dune::array<Dune::FieldMatrix<double,2,6>, 6> backwardStrainDer;
assembler.strainDerivative(backwardSolution, pos, shapeGrad, shapeFunction, backwardStrainDer);
for (int i=0; i<2; i++) {
for (int j=0; j<3; j++) {
for (int m=0; m<3; m++) {
rotationDer[m][i][k][j][l] = (forwardStrainDer[m][i][j]-backwardStrainDer[m][i][j]) / (2*eps);
}
}
}
forwardSolution = x;
backwardSolution = x;
}
}
}
template <class GridType>
void expHessianFD()
{
using namespace Dune;
double eps = 1e-3;
// ///////////////////////////////////////////////////////////
// Compute gradient by finite-difference approximation
// ///////////////////////////////////////////////////////////
FieldVector<double,3> forward;
FieldVector<double,3> backward;
FieldVector<double,3> forwardForward;
FieldVector<double,3> forwardBackward;
FieldVector<double,3> backwardForward;
FieldVector<double,3> backwardBackward;
for (int i=0; i<3; i++) {
for (int j=0; j<3; j++) {
Quaternion<double> hessian;
if (i==j) {
forward = backward = 0;
forward[i] += eps;
backward[i] -= eps;
// Second derivative
// fdHessian[j][k] = (assembler.computeEnergy(forward)
// - 2*assembler.computeEnergy(x)
// + assembler.computeEnergy(backward)) / (eps*eps);
hessian = Rotation<3,double>::exp(forward);
hessian += Rotation<3,double>::exp(backward);
hessian.axpy(-2, Rotation<3,double>::exp(0,0,0));
hessian /= eps*eps;
} else {
forwardForward = forwardBackward = 0;
backwardForward = backwardBackward = 0;
forwardForward[i] += eps;
forwardForward[j] += eps;
forwardBackward[i] += eps;
forwardBackward[j] -= eps;
backwardForward[i] -= eps;
backwardForward[j] += eps;
backwardBackward[i] -= eps;
backwardBackward[j] -= eps;
hessian = Rotation<3,double>::exp(forwardForward);
hessian += Rotation<3,double>::exp(backwardBackward);
hessian -= Rotation<3,double>::exp(forwardBackward);
hessian -= Rotation<3,double>::exp(backwardForward);
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hessian /= 4*eps*eps;
}
printf("i: %d, j: %d ", i, j);
std::cout << hessian << std::endl;
}
}
}
template <class GridType>
void gradientFDCheck(const std::vector<Configuration>& x,
const Dune::BlockVector<Dune::FieldVector<double,6> >& gradient,
const RodAssembler<GridType>& assembler)
{
#ifndef ABORT_ON_ERROR
static int gradientError = 0;
double maxError = -1;
#endif
double eps = 1e-6;
// ///////////////////////////////////////////////////////////
// Compute gradient by finite-difference approximation
// ///////////////////////////////////////////////////////////
std::vector<Configuration> forwardSolution = x;
std::vector<Configuration> backwardSolution = x;
for (size_t i=0; i<x.size(); i++) {
Dune::FieldVector<double,6> fdGradient;
for (int j=0; j<6; j++) {
infinitesimalVariation(forwardSolution[i], eps, j);
infinitesimalVariation(backwardSolution[i], -eps, j);
fdGradient[j] = (assembler.computeEnergy(forwardSolution) - assembler.computeEnergy(backwardSolution))
/ (2*eps);
forwardSolution[i] = x[i];
backwardSolution[i] = x[i];
}
if ( (fdGradient-gradient[i]).two_norm() > 1e-6 ) {
#ifdef ABORT_ON_ERROR
std::cout << "Differing gradients at " << i
<< "! (" << (fdGradient-gradient[i]).two_norm() / gradient[i].two_norm()
<< ") Analytical: " << gradient[i] << ", fd: " << fdGradient << std::endl;
//std::cout << "Current configuration " << std::endl;
for (size_t j=0; j<x.size(); j++)
std::cout << x[j] << std::endl;
//abort();
#else
gradientError++;
maxError = std::max(maxError, (fdGradient-gradient[i]).two_norm());
#endif
}
}
#ifndef ABORT_ON_ERROR
std::cout << gradientError << " errors in the gradient corrected (max: " << maxError << ")!" << std::endl;
#endif
}
template <class GridType>
void hessianFDCheck(const std::vector<Configuration>& x,
const Dune::BCRSMatrix<Dune::FieldMatrix<double,6,6> >& hessian,
const RodAssembler<GridType>& assembler)
{
#ifndef ABORT_ON_ERROR
static int hessianError = 0;
#endif
double eps = 1e-2;
typedef typename Dune::BCRSMatrix<Dune::FieldMatrix<double,6,6> >::row_type::const_iterator ColumnIterator;
// ///////////////////////////////////////////////////////////
// Compute gradient by finite-difference approximation
// ///////////////////////////////////////////////////////////
std::vector<Configuration> forwardSolution = x;
std::vector<Configuration> backwardSolution = x;
std::vector<Configuration> forwardForwardSolution = x;
std::vector<Configuration> forwardBackwardSolution = x;
std::vector<Configuration> backwardForwardSolution = x;
std::vector<Configuration> backwardBackwardSolution = x;
// ///////////////////////////////////////////////////////////////
// Loop over all blocks of the outer matrix
// ///////////////////////////////////////////////////////////////
for (int i=0; i<hessian.N(); i++) {
ColumnIterator cIt = hessian[i].begin();
ColumnIterator cEndIt = hessian[i].end();
for (; cIt!=cEndIt; ++cIt) {
// ////////////////////////////////////////////////////////////////////////////
// Compute a finite-difference approximation of this hessian matrix block
// ////////////////////////////////////////////////////////////////////////////
Dune::FieldMatrix<double,6,6> fdHessian;
for (int j=0; j<6; j++) {
for (int k=0; k<6; k++) {
if (i==cIt.index() && j==k) {
infinitesimalVariation(forwardSolution[i], eps, j);
infinitesimalVariation(backwardSolution[i], -eps, j);
// Second derivative
fdHessian[j][k] = (assembler.computeEnergy(forwardSolution)
+ assembler.computeEnergy(backwardSolution)
- 2*assembler.computeEnergy(x)
) / (eps*eps);
forwardSolution[i] = x[i];
backwardSolution[i] = x[i];
} else {
infinitesimalVariation(forwardForwardSolution[i], eps, j);
infinitesimalVariation(forwardForwardSolution[cIt.index()], eps, k);
infinitesimalVariation(forwardBackwardSolution[i], eps, j);
infinitesimalVariation(forwardBackwardSolution[cIt.index()], -eps, k);
infinitesimalVariation(backwardForwardSolution[i], -eps, j);
infinitesimalVariation(backwardForwardSolution[cIt.index()], eps, k);
infinitesimalVariation(backwardBackwardSolution[i], -eps, j);
infinitesimalVariation(backwardBackwardSolution[cIt.index()],-eps, k);
fdHessian[j][k] = (assembler.computeEnergy(forwardForwardSolution)
+ assembler.computeEnergy(backwardBackwardSolution)
- assembler.computeEnergy(forwardBackwardSolution)
- assembler.computeEnergy(backwardForwardSolution)) / (4*eps*eps);
forwardForwardSolution[i] = x[i];
forwardForwardSolution[cIt.index()] = x[cIt.index()];
forwardBackwardSolution[i] = x[i];
forwardBackwardSolution[cIt.index()] = x[cIt.index()];
backwardForwardSolution[i] = x[i];
backwardForwardSolution[cIt.index()] = x[cIt.index()];
backwardBackwardSolution[i] = x[i];
backwardBackwardSolution[cIt.index()] = x[cIt.index()];
}
}
}
//exit(0);
// /////////////////////////////////////////////////////////////////////////////
// Compare analytical and fd Hessians
// /////////////////////////////////////////////////////////////////////////////
Dune::FieldMatrix<double,6,6> diff = fdHessian;
diff -= *cIt;
if ( diff.frobenius_norm() > 1e-5 ) {
#ifdef ABORT_ON_ERROR
std::cout << "Differing hessians at [(" << i << ", "<< cIt.index() << ")]!" << std::endl
<< "Analytical: " << std::endl << *cIt << std::endl
<< "fd: " << std::endl << fdHessian << std::endl;
abort();
#else
hessianError++;
#endif
}
}
}
#ifndef ABORT_ON_ERROR
std::cout << hessianError << " errors in the Hessian corrected!" << std::endl;
#endif
}
#endif