env_task.hpp

/**
 * A Task class that wraps a continuous RL environment.
 */
template<class EnvironmentType>
class ContinuousRLTask
{
  ContinuousRLTask(EnvironmentType& environment) : environment(environment)
  { /* Nothing to do here */ }

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

    double loss = 0;
    while (!environment.IsTerminal())
    {

      EnvironmentType::Action action;
      action.action[0] = 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;
}