diff options
author | Chris Dyer <redpony@gmail.com> | 2009-12-03 16:33:55 -0500 |
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committer | Chris Dyer <redpony@gmail.com> | 2009-12-03 16:33:55 -0500 |
commit | 671c21451542e2dd20e45b4033d44d8e8735f87b (patch) | |
tree | b1773b077dd65b826f067a423d26f7942ce4e043 /training/model1.cc |
initial check in
Diffstat (limited to 'training/model1.cc')
-rw-r--r-- | training/model1.cc | 103 |
1 files changed, 103 insertions, 0 deletions
diff --git a/training/model1.cc b/training/model1.cc new file mode 100644 index 00000000..f571700f --- /dev/null +++ b/training/model1.cc @@ -0,0 +1,103 @@ +#include <iostream> + +#include "lattice.h" +#include "stringlib.h" +#include "filelib.h" +#include "ttables.h" +#include "tdict.h" + +using namespace std; + +int main(int argc, char** argv) { + if (argc != 2) { + cerr << "Usage: " << argv[0] << " corpus.fr-en\n"; + return 1; + } + const int ITERATIONS = 5; + const prob_t BEAM_THRESHOLD(0.0001); + TTable tt; + const WordID kNULL = TD::Convert("<eps>"); + bool use_null = true; + TTable::Word2Word2Double was_viterbi; + for (int iter = 0; iter < ITERATIONS; ++iter) { + const bool final_iteration = (iter == (ITERATIONS - 1)); + cerr << "ITERATION " << (iter + 1) << (final_iteration ? " (FINAL)" : "") << endl; + ReadFile rf(argv[1]); + istream& in = *rf.stream(); + prob_t likelihood = prob_t::One(); + double denom = 0.0; + int lc = 0; + bool flag = false; + while(true) { + string line; + getline(in, line); + if (!in) break; + ++lc; + if (lc % 1000 == 0) { cerr << '.'; flag = true; } + if (lc %50000 == 0) { cerr << " [" << lc << "]\n" << flush; flag = false; } + string ssrc, strg; + ParseTranslatorInput(line, &ssrc, &strg); + Lattice src, trg; + LatticeTools::ConvertTextToLattice(ssrc, &src); + LatticeTools::ConvertTextToLattice(strg, &trg); + assert(src.size() > 0); + assert(trg.size() > 0); + denom += 1.0; + vector<prob_t> probs(src.size() + 1); + for (int j = 0; j < trg.size(); ++j) { + const WordID& f_j = trg[j][0].label; + prob_t sum = prob_t::Zero(); + if (use_null) { + probs[0] = tt.prob(kNULL, f_j); + sum += probs[0]; + } + for (int i = 1; i <= src.size(); ++i) { + probs[i] = tt.prob(src[i-1][0].label, f_j); + sum += probs[i]; + } + if (final_iteration) { + WordID max_i = 0; + prob_t max_p = prob_t::Zero(); + if (use_null) { + max_i = kNULL; + max_p = probs[0]; + } + for (int i = 1; i <= src.size(); ++i) { + if (probs[i] > max_p) { + max_p = probs[i]; + max_i = src[i-1][0].label; + } + } + was_viterbi[max_i][f_j] = 1.0; + } else { + if (use_null) + tt.Increment(kNULL, f_j, probs[0] / sum); + for (int i = 1; i <= src.size(); ++i) + tt.Increment(src[i-1][0].label, f_j, probs[i] / sum); + } + likelihood *= sum; + } + } + if (flag) { cerr << endl; } + cerr << " log likelihood: " << log(likelihood) << endl; + cerr << " cross entopy: " << (-log(likelihood) / denom) << endl; + cerr << " perplexity: " << pow(2.0, -log(likelihood) / denom) << endl; + if (!final_iteration) tt.Normalize(); + } + for (TTable::Word2Word2Double::iterator ei = tt.ttable.begin(); ei != tt.ttable.end(); ++ei) { + const TTable::Word2Double& cpd = ei->second; + const TTable::Word2Double& vit = was_viterbi[ei->first]; + const string& esym = TD::Convert(ei->first); + prob_t max_p = prob_t::Zero(); + for (TTable::Word2Double::const_iterator fi = cpd.begin(); fi != cpd.end(); ++fi) + if (fi->second > max_p) max_p = prob_t(fi->second); + const prob_t threshold = max_p * BEAM_THRESHOLD; + for (TTable::Word2Double::const_iterator fi = cpd.begin(); fi != cpd.end(); ++fi) { + if (fi->second > threshold || (vit.count(fi->first) > 0)) { + cout << esym << ' ' << TD::Convert(fi->first) << ' ' << log(fi->second) << endl; + } + } + } + return 0; +} + |