neat-task.hpp

neat-task.hpp

/**
 * Main task idea.
 */
class Task
{
  double Evalaute(Genome& genome)
  {
     // This is just a super simple example that shows how to set the input
     // values.
     genome.Input() = arma::vec("1 2 0.3");

     // Calculate the fitness using the output.
     genome.Output();

     double loss = ..;
     return loss
  }
}

/**
 * Task idea that wraps the RL environment.
 */
template<class EnvironmentType>
class Task
{
  Task(EnvironmentType& environment) : environment(environment)
  {
  }

  double Evalaute(Genome& genome)
  {
    // Set the initial state.
    State state = environment.InitialSample();
    genome.Input() = state.Data();

    double loss = 0;
    while (!environment.IsTerminal())
    {
      // In this case we expect that genome.Output()
      // returns a vector of length 1, that does represent
      // the action to take at this state.
      // In case genome will return a vector of length
      // number of actions we could search for the maximum
      // value and return the index of that value in the vector.
      Action action = static_cast<Action>(genome.Output()[0]);

      // Use the current action to get the next state.
      loss += environment.Sample(state, action, state);

      // Update the state of the genome for the next step.
      genome.Input() = state.Data();
    }

    return loss;
  }
 private:
  EnvironmentType environment;
}