in cpp/src/tdigest_accuracy_profile_impl.hpp [32:76]
void tdigest_accuracy_profile<T>::run() {
const unsigned lg_min = 0;
const unsigned lg_max = 23;
const unsigned ppo = 8;
const unsigned num_trials = 1000;
const unsigned error_pct = 99;
const uint16_t compression = 200;
const std::vector<double> ranks = {0.01, 0.05, 0.5, 0.95, 0.99};
std::vector<std::vector<double>> rank_errors(ranks.size(), std::vector<double>());
std::vector<T> values(1ULL << lg_max, 0);
std::cout << "N";
for (const double rank: ranks) std::cout << "\terr at " << rank;
std::cout << "\n";
std::random_device rd;
std::mt19937 gen(rd());
// std::uniform_real_distribution<T> dist(0, 1.0);
std::exponential_distribution<T> dist(1.5);
const unsigned num_steps = count_points(lg_min, lg_max, ppo);
unsigned stream_length = 1 << lg_min;
for (unsigned i = 0; i < num_steps; ++i) {
for (unsigned t = 0; t < num_trials; t++) {
for (size_t j = 0; j < stream_length; ++j) values[j] = dist(gen);
run_trial(values, stream_length, compression, ranks, rank_errors);
}
std::cout << stream_length;
for (auto& errors: rank_errors) {
std::sort(errors.begin(), errors.end());
const size_t error_pct_index = num_trials * error_pct / 100;
const double rank_error = errors[error_pct_index];
std::cout << "\t" << rank_error * 100;
errors.clear();
}
std::cout << "\n";
stream_length = pwr_2_law_next(ppo, stream_length);
}
}