void ParsedInteriorQoI::element_qoi_derivative( AssemblyContext& context,
const unsigned int qoi_index )
{
libMesh::FEBase* element_fe;
context.get_element_fe<libMesh::Real>(0, element_fe);
const std::vector<libMesh::Real> &JxW = element_fe->get_JxW();
const std::vector<libMesh::Point>& x_qp = element_fe->get_xyz();
// Local DOF count and quadrature point count
const unsigned int n_u_dofs = context.get_dof_indices().size();
unsigned int n_qpoints = context.get_element_qrule().n_points();
// Local solution vector - non-const version for finite
// differenting purposes
libMesh::DenseVector<libMesh::Number>& elem_solution =
const_cast<libMesh::DenseVector<libMesh::Number>&>
(context.get_elem_solution());
/*! \todo Need to generalize this to the multiple QoI case */
libMesh::DenseVector<libMesh::Number> &Qu =
context.get_qoi_derivatives()[qoi_index];
for( unsigned int qp = 0; qp != n_qpoints; qp++ )
{
// Central finite differencing to approximate derivatives.
// FIXME - we should hook the FParserAD stuff into
// ParsedFEMFunction
for( unsigned int i = 0; i != n_u_dofs; ++i )
{
libMesh::Number ¤t_solution = elem_solution(i);
const libMesh::Number original_solution = current_solution;
current_solution = original_solution + libMesh::TOLERANCE;
const libMesh::Number plus_val =
(*qoi_functional)(context, x_qp[qp], context.get_time());
current_solution = original_solution - libMesh::TOLERANCE;
const libMesh::Number minus_val =
(*qoi_functional)(context, x_qp[qp], context.get_time());
Qu(i) += (plus_val - minus_val) *
(0.5 / libMesh::TOLERANCE) * JxW[qp];
// Don't forget to restore the correct solution...
current_solution = original_solution;
}
}
}
void AverageNusseltNumber::side_qoi_derivative( AssemblyContext& context,
const unsigned int qoi_index )
{
for( std::set<libMesh::boundary_id_type>::const_iterator id = _bc_ids.begin();
id != _bc_ids.end(); id++ )
{
if( context.has_side_boundary_id( (*id) ) )
{
libMesh::FEBase* T_side_fe;
context.get_side_fe<libMesh::Real>(this->_T_var, T_side_fe);
const std::vector<libMesh::Real> &JxW = T_side_fe->get_JxW();
const std::vector<libMesh::Point>& normals = T_side_fe->get_normals();
unsigned int n_qpoints = context.get_side_qrule().n_points();
const unsigned int n_T_dofs = context.get_dof_indices(_T_var).size();
const std::vector<std::vector<libMesh::Gradient> >& T_gradphi = T_side_fe->get_dphi();
libMesh::DenseSubVector<libMesh::Number>& dQ_dT =
context.get_qoi_derivatives(qoi_index, _T_var);
// Loop over quadrature points
for (unsigned int qp = 0; qp != n_qpoints; qp++)
{
// Get the solution value at the quadrature point
libMesh::Gradient grad_T = 0.0;
context.side_gradient(this->_T_var, qp, grad_T);
// Update the elemental increment dR for each qp
//qoi += (this->_scaling)*(this->_k)*(grad_T*normals[qp])*JxW[qp];
for( unsigned int i = 0; i != n_T_dofs; i++ )
{
dQ_dT(i) += _scaling*_k*T_gradphi[i][qp]*normals[qp]*JxW[qp];
}
} // quadrature loop
} // end check on boundary id
}
return;
}
