#include <iostream> #include <vector> #include <boost/program_options.hpp> #include "prob.h" #include "tdict.h" #include "scorer.h" #include "filelib.h" #include "stringlib.h" using namespace std; namespace po = boost::program_options; void InitCommandLine(int argc, char** argv, po::variables_map* conf) { po::options_description opts("Configuration options"); opts.add_options() ("scale,a",po::value<double>()->default_value(1.0), "Posterior scaling factor (alpha)") ("loss_function,l",po::value<string>()->default_value("bleu"), "Loss function") ("input,i",po::value<string>()->default_value("-"), "File to read k-best lists from") ("output_list,L", "Show reranked list as output") ("help,h", "Help"); po::options_description dcmdline_options; dcmdline_options.add(opts); po::store(parse_command_line(argc, argv, dcmdline_options), *conf); bool flag = false; if (flag || conf->count("help")) { cerr << dcmdline_options << endl; exit(1); } } struct LossComparer { bool operator()(const pair<vector<WordID>, double>& a, const pair<vector<WordID>, double>& b) const { return a.second < b.second; } }; bool ReadKBestList(istream* in, string* sent_id, vector<pair<vector<WordID>, prob_t> >* list) { static string cache_id; static pair<vector<WordID>, prob_t> cache_pair; list->clear(); string cur_id; if (cache_pair.first.size() > 0) { list->push_back(cache_pair); cur_id = cache_id; cache_pair.first.clear(); } string line; string tstr; while(*in) { getline(*in, line); if (line.empty()) continue; size_t p1 = line.find(" ||| "); if (p1 == string::npos) { cerr << "Bad format: " << line << endl; abort(); } size_t p2 = line.find(" ||| ", p1 + 4); if (p2 == string::npos) { cerr << "Bad format: " << line << endl; abort(); } size_t p3 = line.rfind(" ||| "); cache_id = line.substr(0, p1); tstr = line.substr(p1 + 5, p2 - p1 - 5); double val = strtod(line.substr(p3 + 5).c_str(), NULL); TD::ConvertSentence(tstr, &cache_pair.first); cache_pair.second.logeq(val); if (cur_id.empty()) cur_id = cache_id; if (cur_id == cache_id) { list->push_back(cache_pair); *sent_id = cur_id; cache_pair.first.clear(); } else { break; } } return !list->empty(); } int main(int argc, char** argv) { po::variables_map conf; InitCommandLine(argc, argv, &conf); const string metric = conf["loss_function"].as<string>(); const bool output_list = conf.count("output_list") > 0; const string file = conf["input"].as<string>(); const double mbr_scale = conf["scale"].as<double>(); cerr << "Posterior scaling factor (alpha) = " << mbr_scale << endl; ScoreType type = ScoreTypeFromString(metric); vector<pair<vector<WordID>, prob_t> > list; ReadFile rf(file); string sent_id; while(ReadKBestList(rf.stream(), &sent_id, &list)) { vector<prob_t> joints(list.size()); const prob_t max_score = pow(list.front().second, mbr_scale); prob_t marginal = prob_t::Zero(); for (int i = 0 ; i < list.size(); ++i) { const prob_t joint = pow(list[i].second, mbr_scale) / max_score; joints[i] = joint; // cerr << "list[" << i << "] joint=" << log(joint) << endl; marginal += joint; } int mbr_idx = -1; vector<double> mbr_scores(output_list ? list.size() : 0); double mbr_loss = numeric_limits<double>::max(); for (int i = 0 ; i < list.size(); ++i) { vector<vector<WordID> > refs(1, list[i].first); //cerr << i << ": " << list[i].second <<"\t" << TD::GetString(list[i].first) << endl; ScorerP scorer = SentenceScorer::CreateSentenceScorer(type, refs); double wl_acc = 0; for (int j = 0; j < list.size(); ++j) { if (i != j) { ScoreP s = scorer->ScoreCandidate(list[j].first); double loss = 1.0 - s->ComputeScore(); if (type == TER || type == AER) loss = 1.0 - loss; double weighted_loss = loss * (joints[j] / marginal); wl_acc += weighted_loss; if ((!output_list) && wl_acc > mbr_loss) break; } } if (output_list) mbr_scores[i] = wl_acc; if (wl_acc < mbr_loss) { mbr_loss = wl_acc; mbr_idx = i; } } // cerr << "ML translation: " << TD::GetString(list[0].first) << endl; cerr << "MBR Best idx: " << mbr_idx << endl; if (output_list) { for (int i = 0; i < list.size(); ++i) list[i].second.logeq(mbr_scores[i]); sort(list.begin(), list.end(), LossComparer()); for (int i = 0; i < list.size(); ++i) cout << sent_id << " ||| " << TD::GetString(list[i].first) << " ||| " << log(list[i].second) << endl; } else { cout << TD::GetString(list[mbr_idx].first) << endl; } } return 0; }