Function main

contents/cooley_tukey/code/cpp/fft.cpp:109–136

}

int main() {
  // initalize the FFT inputs
  std::random_device random_device;
  std::mt19937 rng(random_device());
  std::uniform_real_distribution<double> distribution(0.0, 1.0);

  std::array<complex, 64> initial;
  std::generate(
      begin(initial), end(initial), [&] { return distribution(rng); });

  auto recursive = initial;
  auto iterative = initial;

  // Preform an FFT on the arrays.
  cooley_tukey(begin(recursive), end(recursive));
  iterative_cooley_tukey(begin(iterative), end(iterative));

  // Check if the arrays are approximately equivalent
  std::cout << std::right << std::setw(16) << "idx" << std::setw(16) << "rec"
            << std::setw(16) << "it" << std::setw(16) << "subtracted" << '\n';
  for (size_t i = 0; i < initial.size(); ++i) {
    auto rec = recursive[i];
    auto it = iterative[i];
    std::cout << std::setw(16) << i << std::setw(16) << std::abs(rec)
              << std::setw(16) << std::abs(it) << std::setw(16)
              << (std::abs(rec) - std::abs(it)) << '\n';
  }
}