buffer.hpp

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#ifndef BUFFER_HPP
#define BUFFER_HPP
 
#include <unordered_map>
#include <armadillo>
 
namespace ergodic_exploration
{
using arma::mat;
using arma::vec;
 
class ReplayBuffer
{
public:
  ReplayBuffer(unsigned int buffer_size, unsigned int batch_size);
 
  void append(const vec& x);
 
  mat sampleMemory(const mat& xt) const;
 
private:
  unsigned int buffer_size_;                      // total number of past states in memory
  unsigned int batch_size_;                       // number of states sampled from memory
  std::unordered_map<unsigned int, vec> memory_;  // past states
};
}  // namespace ergodic_exploration
#endif