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Diffstat (limited to 'training/fast_align.cc')
-rw-r--r-- | training/fast_align.cc | 281 |
1 files changed, 0 insertions, 281 deletions
diff --git a/training/fast_align.cc b/training/fast_align.cc deleted file mode 100644 index 7492d26f..00000000 --- a/training/fast_align.cc +++ /dev/null @@ -1,281 +0,0 @@ -#include <iostream> -#include <cmath> - -#include <boost/program_options.hpp> -#include <boost/program_options/variables_map.hpp> - -#include "m.h" -#include "corpus_tools.h" -#include "stringlib.h" -#include "filelib.h" -#include "ttables.h" -#include "tdict.h" - -namespace po = boost::program_options; -using namespace std; - -bool InitCommandLine(int argc, char** argv, po::variables_map* conf) { - po::options_description opts("Configuration options"); - opts.add_options() - ("input,i",po::value<string>(),"Parallel corpus input file") - ("reverse,r","Reverse estimation (swap source and target during training)") - ("iterations,I",po::value<unsigned>()->default_value(5),"Number of iterations of EM training") - //("bidir,b", "Run bidirectional alignment") - ("favor_diagonal,d", "Use a static alignment distribution that assigns higher probabilities to alignments near the diagonal") - ("prob_align_null", po::value<double>()->default_value(0.08), "When --favor_diagonal is set, what's the probability of a null alignment?") - ("diagonal_tension,T", po::value<double>()->default_value(4.0), "How sharp or flat around the diagonal is the alignment distribution (<1 = flat >1 = sharp)") - ("variational_bayes,v","Infer VB estimate of parameters under a symmetric Dirichlet prior") - ("alpha,a", po::value<double>()->default_value(0.01), "Hyperparameter for optional Dirichlet prior") - ("no_null_word,N","Do not generate from a null token") - ("output_parameters,p", "Write model parameters instead of alignments") - ("beam_threshold,t",po::value<double>()->default_value(-4),"When writing parameters, log_10 of beam threshold for writing parameter (-10000 to include everything, 0 max parameter only)") - ("hide_training_alignments,H", "Hide training alignments (only useful if you want to use -x option and just compute testset statistics)") - ("testset,x", po::value<string>(), "After training completes, compute the log likelihood of this set of sentence pairs under the learned model") - ("no_add_viterbi,V","When writing model parameters, do not add Viterbi alignment points (may generate a grammar where some training sentence pairs are unreachable)"); - po::options_description clo("Command line options"); - clo.add_options() - ("config", po::value<string>(), "Configuration file") - ("help,h", "Print this help message and exit"); - po::options_description dconfig_options, dcmdline_options; - dconfig_options.add(opts); - dcmdline_options.add(opts).add(clo); - - po::store(parse_command_line(argc, argv, dcmdline_options), *conf); - if (conf->count("config")) { - ifstream config((*conf)["config"].as<string>().c_str()); - po::store(po::parse_config_file(config, dconfig_options), *conf); - } - po::notify(*conf); - - if (conf->count("help") || conf->count("input") == 0) { - cerr << "Usage " << argv[0] << " [OPTIONS] -i corpus.fr-en\n"; - cerr << dcmdline_options << endl; - return false; - } - return true; -} - -int main(int argc, char** argv) { - po::variables_map conf; - if (!InitCommandLine(argc, argv, &conf)) return 1; - const string fname = conf["input"].as<string>(); - const bool reverse = conf.count("reverse") > 0; - const int ITERATIONS = conf["iterations"].as<unsigned>(); - const double BEAM_THRESHOLD = pow(10.0, conf["beam_threshold"].as<double>()); - const bool use_null = (conf.count("no_null_word") == 0); - const WordID kNULL = TD::Convert("<eps>"); - const bool add_viterbi = (conf.count("no_add_viterbi") == 0); - const bool variational_bayes = (conf.count("variational_bayes") > 0); - const bool write_alignments = (conf.count("output_parameters") == 0); - const double diagonal_tension = conf["diagonal_tension"].as<double>(); - const double prob_align_null = conf["prob_align_null"].as<double>(); - const bool hide_training_alignments = (conf.count("hide_training_alignments") > 0); - string testset; - if (conf.count("testset")) testset = conf["testset"].as<string>(); - const double prob_align_not_null = 1.0 - prob_align_null; - const double alpha = conf["alpha"].as<double>(); - const bool favor_diagonal = conf.count("favor_diagonal"); - if (variational_bayes && alpha <= 0.0) { - cerr << "--alpha must be > 0\n"; - return 1; - } - - TTable s2t, t2s; - TTable::Word2Word2Double s2t_viterbi; - double tot_len_ratio = 0; - double mean_srclen_multiplier = 0; - vector<double> unnormed_a_i; - for (int iter = 0; iter < ITERATIONS; ++iter) { - const bool final_iteration = (iter == (ITERATIONS - 1)); - cerr << "ITERATION " << (iter + 1) << (final_iteration ? " (FINAL)" : "") << endl; - ReadFile rf(fname); - istream& in = *rf.stream(); - double likelihood = 0; - double denom = 0.0; - int lc = 0; - bool flag = false; - string line; - string ssrc, strg; - vector<WordID> src, trg; - while(true) { - getline(in, line); - if (!in) break; - ++lc; - if (lc % 1000 == 0) { cerr << '.'; flag = true; } - if (lc %50000 == 0) { cerr << " [" << lc << "]\n" << flush; flag = false; } - src.clear(); trg.clear(); - CorpusTools::ReadLine(line, &src, &trg); - if (reverse) swap(src, trg); - if (src.size() == 0 || trg.size() == 0) { - cerr << "Error: " << lc << "\n" << line << endl; - return 1; - } - if (src.size() > unnormed_a_i.size()) - unnormed_a_i.resize(src.size()); - if (iter == 0) - tot_len_ratio += static_cast<double>(trg.size()) / static_cast<double>(src.size()); - denom += trg.size(); - vector<double> probs(src.size() + 1); - bool first_al = true; // used for write_alignments - for (int j = 0; j < trg.size(); ++j) { - const WordID& f_j = trg[j]; - double sum = 0; - const double j_over_ts = double(j) / trg.size(); - double prob_a_i = 1.0 / (src.size() + use_null); // uniform (model 1) - if (use_null) { - if (favor_diagonal) prob_a_i = prob_align_null; - probs[0] = s2t.prob(kNULL, f_j) * prob_a_i; - sum += probs[0]; - } - double az = 0; - if (favor_diagonal) { - for (int ta = 0; ta < src.size(); ++ta) { - unnormed_a_i[ta] = exp(-fabs(double(ta) / src.size() - j_over_ts) * diagonal_tension); - az += unnormed_a_i[ta]; - } - az /= prob_align_not_null; - } - for (int i = 1; i <= src.size(); ++i) { - if (favor_diagonal) - prob_a_i = unnormed_a_i[i-1] / az; - probs[i] = s2t.prob(src[i-1], f_j) * prob_a_i; - sum += probs[i]; - } - if (final_iteration) { - if (add_viterbi || write_alignments) { - WordID max_i = 0; - double max_p = -1; - int max_index = -1; - if (use_null) { - max_i = kNULL; - max_index = 0; - max_p = probs[0]; - } - for (int i = 1; i <= src.size(); ++i) { - if (probs[i] > max_p) { - max_index = i; - max_p = probs[i]; - max_i = src[i-1]; - } - } - if (!hide_training_alignments && write_alignments) { - if (max_index > 0) { - if (first_al) first_al = false; else cout << ' '; - if (reverse) - cout << j << '-' << (max_index - 1); - else - cout << (max_index - 1) << '-' << j; - } - } - s2t_viterbi[max_i][f_j] = 1.0; - } - } else { - if (use_null) - s2t.Increment(kNULL, f_j, probs[0] / sum); - for (int i = 1; i <= src.size(); ++i) - s2t.Increment(src[i-1], f_j, probs[i] / sum); - } - likelihood += log(sum); - } - if (write_alignments && final_iteration && !hide_training_alignments) cout << endl; - } - - // log(e) = 1.0 - double base2_likelihood = likelihood / log(2); - - if (flag) { cerr << endl; } - if (iter == 0) { - mean_srclen_multiplier = tot_len_ratio / lc; - cerr << "expected target length = source length * " << mean_srclen_multiplier << endl; - } - cerr << " log_e likelihood: " << likelihood << endl; - cerr << " log_2 likelihood: " << base2_likelihood << endl; - cerr << " cross entropy: " << (-base2_likelihood / denom) << endl; - cerr << " perplexity: " << pow(2.0, -base2_likelihood / denom) << endl; - if (!final_iteration) { - if (variational_bayes) - s2t.NormalizeVB(alpha); - else - s2t.Normalize(); - } - } - if (testset.size()) { - ReadFile rf(testset); - istream& in = *rf.stream(); - int lc = 0; - double tlp = 0; - string line; - while (getline(in, line)) { - ++lc; - vector<WordID> src, trg; - CorpusTools::ReadLine(line, &src, &trg); - cout << TD::GetString(src) << " ||| " << TD::GetString(trg) << " |||"; - if (reverse) swap(src, trg); - double log_prob = Md::log_poisson(trg.size(), 0.05 + src.size() * mean_srclen_multiplier); - if (src.size() > unnormed_a_i.size()) - unnormed_a_i.resize(src.size()); - - // compute likelihood - for (int j = 0; j < trg.size(); ++j) { - const WordID& f_j = trg[j]; - double sum = 0; - int a_j = 0; - double max_pat = 0; - const double j_over_ts = double(j) / trg.size(); - double prob_a_i = 1.0 / (src.size() + use_null); // uniform (model 1) - if (use_null) { - if (favor_diagonal) prob_a_i = prob_align_null; - max_pat = s2t.prob(kNULL, f_j) * prob_a_i; - sum += max_pat; - } - double az = 0; - if (favor_diagonal) { - for (int ta = 0; ta < src.size(); ++ta) { - unnormed_a_i[ta] = exp(-fabs(double(ta) / src.size() - j_over_ts) * diagonal_tension); - az += unnormed_a_i[ta]; - } - az /= prob_align_not_null; - } - for (int i = 1; i <= src.size(); ++i) { - if (favor_diagonal) - prob_a_i = unnormed_a_i[i-1] / az; - double pat = s2t.prob(src[i-1], f_j) * prob_a_i; - if (pat > max_pat) { max_pat = pat; a_j = i; } - sum += pat; - } - log_prob += log(sum); - if (write_alignments) { - if (a_j > 0) { - cout << ' '; - if (reverse) - cout << j << '-' << (a_j - 1); - else - cout << (a_j - 1) << '-' << j; - } - } - } - tlp += log_prob; - cout << " ||| " << log_prob << endl << flush; - } // loop over test set sentences - cerr << "TOTAL LOG PROB " << tlp << endl; - } - - if (write_alignments) return 0; - - for (TTable::Word2Word2Double::iterator ei = s2t.ttable.begin(); ei != s2t.ttable.end(); ++ei) { - const TTable::Word2Double& cpd = ei->second; - const TTable::Word2Double& vit = s2t_viterbi[ei->first]; - const string& esym = TD::Convert(ei->first); - double max_p = -1; - for (TTable::Word2Double::const_iterator fi = cpd.begin(); fi != cpd.end(); ++fi) - if (fi->second > max_p) max_p = fi->second; - const double threshold = max_p * BEAM_THRESHOLD; - for (TTable::Word2Double::const_iterator fi = cpd.begin(); fi != cpd.end(); ++fi) { - if (fi->second > threshold || (vit.find(fi->first) != vit.end())) { - cout << esym << ' ' << TD::Convert(fi->first) << ' ' << log(fi->second) << endl; - } - } - } - return 0; -} - |