basis.hpp

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#ifndef BASIS_HPP
#define BASIS_HPP
 
#include <armadillo>
 
namespace ergodic_exploration
{
using arma::imat;
using arma::mat;
using arma::vec;
 
class Basis
{
private:
  template <class ModelT>
  friend class ErgodicControl;
 
public:
  Basis(double lx, double ly, unsigned int num_basis);
 
  vec fourierBasis(const vec& x) const;
 
  mat gradFourierBasis(const vec& x) const;
 
  vec trajCoeff(const mat& xt) const;
 
  vec spatialCoeff(const vec& phi_vals, const mat& phi_grid) const;
 
private:
  double lx_, ly_;            // length of domain
  unsigned int total_basis_;  // number of basis functions
  vec lamdak_;                // frequency coefficients weights
  imat k_;                    // basis number
};
}  // namespace ergodic_exploration
#endif