biharmonic3d.h

//
// Created by RainSure on 2024/2/22.
//
 
#ifndef RSMESH_BIHARMONIC3D_H
#define RSMESH_BIHARMONIC3D_H
 
#include "rbf_base.h"
 
namespace rsmesh::rbf {
    class biharmonic3d final : public rbf_base {
    public:
        using rbf_base::rbf_base;
 
        explicit biharmonic3d(const std::vector<double>& params) { set_parameters(params); }
 
        [[nodiscard]] std::unique_ptr<rbf_base> clone() const override { return std::make_unique<biharmonic3d>(*this); }
 
        [[nodiscard]] int cpd_order() const override { return 1; }
 
        [[nodiscard]] double evaluate_isotropic(const vector3d& diff) const override {
            auto slope = parameters().at(0);
            auto r = diff.norm();
 
            return -slope * r;
        }
 
        [[nodiscard]] vector3d evaluate_gradient_isotropic(const vector3d& /*diff*/) const override {
            throw std::runtime_error("biharmonic3d::evaluate_gradient_isotropic() is not implemented");
        }
 
        [[nodiscard]] matrix3d evaluate_hessian_isotropic(const vector3d& /*diff*/) const override {
            throw std::runtime_error("biharmonic3d::evaluate_hessian_isotropic() is not implemented");
        }
 
        [[nodiscard]] int num_parameters() const override { return 1; }
 
        [[nodiscard]] const std::vector<double>& parameter_lower_bounds() const override {
            static const std::vector<double> lower_bounds{0.0};
            return lower_bounds;
        }
 
        [[nodiscard]] const std::vector<double>& parameter_upper_bounds() const override {
            static const std::vector<double> upper_bounds{std::numeric_limits<double>::infinity()};
            return upper_bounds;
        }
    };
 
} // namespace rsmesh::rbf
 
#endif //RSMESH_BIHARMONIC3D_H