Commit fc7919fb authored by Nguyen, Thien Minh's avatar Nguyen, Thien Minh
Browse files

Implemented Tim P's recommendations 



- Rescale the success probs.

- Report the mean and min of rescale success probs.

Signed-off-by: default avatarThien Nguyen <nguyentm@ornl.gov>
parent 80e383a0

lib/mirror_rb/mirror_circuit_rb.cpp

+28 −1
Original line number Diff line number Diff line
@@ -237,23 +237,50 @@ std::pair<bool, xacc::HeterogeneousMap> MirrorCircuitValidator::validate( 


    auto mc_buffer = xacc::qalloc(mirror_circuit->nPhysicalBits());

    qpu->execute(mc_buffer, mirror_circuit->as_xacc());

    static const auto f_P_S = [](double S, size_t n) -> double {

      const int64_t dim = std::pow(2, n);

      const double P_S = (1.0 - 1.0 / dim) / (S - 1.0 / dim);

      return P_S;

    };

    static const auto f_S_P = [](double S, size_t n) -> double {

      const int64_t dim = std::pow(2, n);

      const double S_P = (S - 1.0 / dim) / (1.0 - 1.0 / dim);

      return S_P;

    };

    {

      std::stringstream ss;

      ss << "Trial " << i << "\n";

      ss << "Circuit:\n" << mirror_circuit->toString() << "\n";

      ss << "Result:\n" << mc_buffer->toString() << "\n";

      ss << "Expected bitstring:" << expectedBitString << "\n";

      const auto S =

          mc_buffer->computeMeasurementProbability(expectedBitString);

      ss << "S:" << S << "\n";

      const auto P_prime = std::sqrt(f_S_P(S, mc_buffer->size()));

      ss << "P':" << P_prime << "\n";

      const auto S_prime = f_P_S(P_prime, mc_buffer->size()); 

      ss << "S':" << S_prime << "\n";

      xacc::info(ss.str());

    }

    const auto bitStrProb =

        mc_buffer->computeMeasurementProbability(expectedBitString);

    trial_success_probs.emplace_back(bitStrProb);

    trial_success_probs.emplace_back(

        std::sqrt(f_S_P(bitStrProb, mc_buffer->size())));

  }

  xacc::HeterogeneousMap data;

  data.insert("trial-success-probabilities", trial_success_probs);

  const bool pass_fail_result =

      std::all_of(trial_success_probs.begin(), trial_success_probs.end(),

                  [&eps](double val) { return val > 1.0 - eps; });

  std::cout << "Mean(P') = "

            << std::accumulate(trial_success_probs.begin(),

                               trial_success_probs.end(), 0.0) /

                   trial_success_probs.size()

            << "\n";

  std::cout << "Min(P') = "

            << *std::min_element(trial_success_probs.begin(),

                                 trial_success_probs.end())

            << "\n";

  return std::make_pair(pass_fail_result, data);

}