Dense.hpp

Go to the documentation of this file.

 
#pragma once
 
#include <string>
#include <utility>
 
#include <Eigen/Dense>
 
#include "LayerTypes.hpp"
#include "activations/Activation.hpp"
#include "activations/ActivationParameters.hpp"
 
namespace FlexNN::Layers {
 
class Dense {
 public:
  Dense(int in, int out,
        Activations::Activation act = Activations::Activation::ReLU,
        const Activations::ActivationParameters& params = Activations::ActivationParameters{});
 
  explicit Dense(DenseParams p,
                 Activations::Activation act = Activations::Activation::ReLU,
                 const Activations::ActivationParameters& params = Activations::ActivationParameters{});
 
  [[deprecated("use Activations::Activation enum")]]
  Dense(int in, int out, const std::string& actStr);
 
  // Accessors — used by NeuralNetwork and ModelIO via visit.
  LayerType type() const noexcept { return LayerType::Dense; }
  Activations::Activation activation() const noexcept { return act_; }
  const Activations::ActivationParameters& activationParams() const noexcept { return actParams_; }
  const DenseParams& params() const noexcept { return params_; }
  const Eigen::MatrixXd& weights() const noexcept { return W_; }
  const Eigen::VectorXd& biases() const noexcept { return b_; }
 
  // Mutators for importModel (replaces weights after allocation).
  void setWeights(const Eigen::MatrixXd& W) { W_ = W; }
  void setBiases(const Eigen::VectorXd& b) { b_ = b; }
  void setActivationParameters(const Activations::ActivationParameters& p) { actParams_ = p; }
 
  std::pair<Eigen::MatrixXd, Eigen::MatrixXd> forward(
      const Eigen::MatrixXd& input) const;
 
  Eigen::MatrixXd backward(const Eigen::MatrixXd& nextW,
                           const Eigen::MatrixXd& nextdZ,
                           const Eigen::MatrixXd& currZ) const;
 
  Eigen::MatrixXd backward(const Eigen::MatrixXd& upstream,
                           const Eigen::MatrixXd& currZ) const;
 
  Eigen::MatrixXd propagate(const Eigen::MatrixXd& dZ) const;
 
  void update(const Eigen::MatrixXd& dW, const Eigen::VectorXd& db,
              double lr) noexcept;
 
 private:
  DenseParams params_{};
  Activations::Activation act_ = Activations::Activation::ReLU;
  Activations::ActivationParameters actParams_{};
  Eigen::MatrixXd W_; 
  Eigen::VectorXd b_; 
};
 
} // namespace FlexNN::Layers