Line data    Source code

       1             : #include "NewtonRaphson.h"
       2             : #include "TypeCasts.hpp"
       3             : 
       4             : namespace elsa
       5             : {
       6             : 
       7             :     template <class data_t>
       8             :     NewtonRaphson<data_t>::NewtonRaphson(const Functional<data_t>& f, index_t iterations)
       9             :         : LineSearchMethod<data_t>(f), iters_(iterations)
      10           2 :     {
      11           2 :     }
      12             : 
      13             :     template <class data_t>
      14             :     data_t NewtonRaphson<data_t>::solve(DataContainer<data_t> xi, DataContainer<data_t> di)
      15           2 :     {
      16           2 :         auto alpha = data_t{-1.0} * this->_problem->getGradient(xi).dot(di)
      17           2 :                      / di.dot(this->_problem->getHessian(xi).apply(di));
      18             : 
      19           2 :         for (int i = 1; i < iters_; ++i) {
      20           0 :             xi = xi + alpha * di;
      21             : 
      22           0 :             alpha = data_t{-1.0} * this->_problem->getGradient(xi).dot(di)
      23           0 :                     / di.dot(this->_problem->getHessian(xi).apply(di));
      24           0 :         }
      25             : 
      26           2 :         return alpha;
      27           2 :     }
      28             : 
      29             :     /// implement the polymorphic comparison operation
      30             :     template <class data_t>
      31             :     bool NewtonRaphson<data_t>::isEqual(const LineSearchMethod<data_t>& other) const
      32           0 :     {
      33           0 :         auto tmp = downcast_safe<NewtonRaphson<data_t>>(&other);
      34           0 :         return static_cast<bool>(tmp);
      35           0 :     }
      36             : 
      37             :     template <class data_t>
      38             :     NewtonRaphson<data_t>* NewtonRaphson<data_t>::cloneImpl() const
      39           0 :     {
      40           0 :         return new NewtonRaphson(*this->_problem, iters_);
      41           0 :     }
      42             : 
      43             :     // ------------------------------------------
      44             :     // explicit template instantiation
      45             :     template class NewtonRaphson<float>;
      46             :     template class NewtonRaphson<double>;
      47             : } // namespace elsa