det_by_minor.hpp

Source: det_by_minor

# ifndef CPPAD_DET_BY_MINOR_HPP
# define CPPAD_DET_BY_MINOR_HPP
# include <cppad/speed/det_of_minor.hpp>
# include <vector>

// BEGIN CppAD namespace
namespace CppAD {

template <class Scalar>
class det_by_minor {
private:
   size_t              m_;

   // made mutable because modified and then restored
   mutable std::vector<size_t> r_;
   mutable std::vector<size_t> c_;

   // make mutable because its value does not matter
   mutable std::vector<Scalar> a_;
public:
   det_by_minor(size_t m) : m_(m) , r_(m + 1) , c_(m + 1), a_(m * m)
   {
      size_t i;

      // values for r and c that correspond to entire matrix
      for(i = 0; i < m; i++)
      {  r_[i] = i+1;
         c_[i] = i+1;
      }
      r_[m] = 0;
      c_[m] = 0;
   }

   template <class Vector>
   Scalar operator()(const Vector &x) const
   {  size_t i = m_ * m_;
      while(i--)
         a_[i] = x[i];
      return det_of_minor(a_, m_, m_, r_, c_);
   }

};

} // END CppAD namespace

# endif