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#include "dtrain.h"
#include "sample.h"
#include "score.h"
#include "update.h"
using namespace dtrain;
int
main(int argc, char** argv)
{
// get configuration
po::variables_map conf;
if (!dtrain_init(argc, argv, &conf))
return 1;
const size_t k = conf["k"].as<size_t>();
const bool unique_kbest = conf["unique_kbest"].as<bool>();
const bool forest_sample = conf["forest_sample"].as<bool>();
const string score_name = conf["score"].as<string>();
const weight_t nakov_fix = conf["nakov_fix"].as<weight_t>();
const weight_t chiang_decay = conf["chiang_decay"].as<weight_t>();
const size_t N = conf["N"].as<size_t>();
const size_t T = conf["iterations"].as<size_t>();
const weight_t eta = conf["learning_rate"].as<weight_t>();
const weight_t margin = conf["margin"].as<weight_t>();
const weight_t cut = conf["cut"].as<weight_t>();
const bool adjust_cut = conf["adjust"].as<bool>();
const bool all_pairs = cut==0;
const bool average = conf["average"].as<bool>();
const bool pro = conf["pro_sampling"].as<bool>();
const bool structured = conf["structured"].as<bool>();
const weight_t threshold = conf["threshold"].as<weight_t>();
const size_t max_up = conf["max_pairs"].as<size_t>();
const weight_t l1_reg = conf["l1_reg"].as<weight_t>();
const bool keep = conf["keep"].as<bool>();
const bool noup = conf["disable_learning"].as<bool>();
const string output_fn = conf["output"].as<string>();
vector<string> print_weights;
boost::split(print_weights, conf["print_weights"].as<string>(),
boost::is_any_of(" "));
const string output_updates_fn = conf["output_updates"].as<string>();
const bool output_updates = output_updates_fn!="";
const string output_raw_fn = conf["output_raw"].as<string>();
const bool output_raw = output_raw_fn!="";
const bool use_adadelta = conf["adadelta"].as<bool>();
const weight_t adadelta_decay = conf["adadelta_decay"].as<weight_t>();
const weight_t adadelta_eta = 0.000001;
const string adadelta_input = conf["adadelta_input"].as<string>();
const string adadelta_output = conf["adadelta_output"].as<string>();
const size_t max_input = conf["stop_after"].as<size_t>();
const bool batch = conf["batch"].as<bool>();
// setup decoder
register_feature_functions();
SetSilent(true);
ReadFile f(conf["decoder_conf"].as<string>());
Decoder decoder(f.stream());
// setup scorer & observer
Scorer* scorer;
if (score_name == "nakov") {
scorer = static_cast<NakovBleuScorer*>(new NakovBleuScorer(N, nakov_fix));
} else if (score_name == "papineni") {
scorer = static_cast<PapineniBleuScorer*>(new PapineniBleuScorer(N));
} else if (score_name == "lin") {
scorer = static_cast<LinBleuScorer*>(new LinBleuScorer(N));
} else if (score_name == "liang") {
scorer = static_cast<LiangBleuScorer*>(new LiangBleuScorer(N));
} else if (score_name == "chiang") {
scorer = static_cast<ChiangBleuScorer*>(new ChiangBleuScorer(N));
} else if (score_name == "sum") {
scorer = static_cast<SumBleuScorer*>(new SumBleuScorer(N));
} else {
assert(false);
}
HypSampler* observer;
if (forest_sample)
observer = new KSampler(k, scorer);
else if (unique_kbest)
observer = new KBestSampler(k, scorer);
else
observer = new KBestNoFilterSampler(k, scorer);
// weights
vector<weight_t>& decoder_weights = decoder.CurrentWeightVector();
SparseVector<weight_t> lambdas, w_average;
if (conf.count("input_weights")) {
Weights::InitFromFile(conf["input_weights"].as<string>(), &decoder_weights);
Weights::InitSparseVector(decoder_weights, &lambdas);
}
// input
string input_fn = conf["bitext"].as<string>();
ReadFile input(input_fn);
vector<string> buf; // decoder only accepts strings as input
vector<vector<Ngrams> > buffered_ngrams; // compute ngrams and lengths of references
vector<vector<size_t> > buffered_lengths; // (just once)
size_t input_sz = 0;
// output configuration
cerr << fixed << setprecision(4);
cerr << "Parameters:" << endl;
cerr << setw(25) << "bitext " << "'" << input_fn << "'" << endl;
cerr << setw(25) << "k " << k << endl;
if (unique_kbest && !forest_sample)
cerr << setw(25) << "unique k-best " << unique_kbest << endl;
if (forest_sample)
cerr << setw(25) << "forest " << forest_sample << endl;
if (all_pairs)
cerr << setw(25) << "all pairs " << all_pairs << endl;
else if (pro)
cerr << setw(25) << "PRO " << pro << endl;
cerr << setw(25) << "score " << "'" << score_name << "'" << endl;
if (score_name == "nakov")
cerr << setw(25) << "nakov fix " << nakov_fix << endl;
if (score_name == "chiang")
cerr << setw(25) << "chiang decay " << chiang_decay << endl;
cerr << setw(25) << "N " << N << endl;
cerr << setw(25) << "T " << T << endl;
cerr << scientific << setw(25) << "learning rate " << eta << endl;
cerr << setw(25) << "margin " << margin << endl;
if (!structured) {
cerr << fixed << setw(25) << "cut " << round(cut*100) << "%" << endl;
cerr << setw(25) << "adjust " << adjust_cut << endl;
} else {
cerr << setw(25) << "struct. obj " << structured << endl;
}
if (threshold > 0)
cerr << setw(25) << "threshold " << threshold << endl;
if (max_up != numeric_limits<size_t>::max())
cerr << setw(25) << "max up. " << max_up << endl;
if (noup)
cerr << setw(25) << "no up. " << noup << endl;
cerr << setw(25) << "average " << average << endl;
cerr << scientific << setw(25) << "l1 reg. " << l1_reg << endl;
cerr << setw(25) << "decoder conf " << "'"
<< conf["decoder_conf"].as<string>() << "'" << endl;
cerr << setw(25) << "input " << "'" << input_fn << "'" << endl;
cerr << setw(25) << "output " << "'" << output_fn << "'" << endl;
if (conf.count("input_weights")) {
cerr << setw(25) << "weights in " << "'"
<< conf["input_weights"].as<string>() << "'" << endl;
}
cerr << setw(25) << "batch " << batch << endl;
if (noup)
cerr << setw(25) << "no updates!" << endl;
if (use_adadelta) {
cerr << setw(25) << "adadelta " << use_adadelta << endl;
cerr << setw(25) << " decay " << adadelta_decay << endl;
if (adadelta_input != "")
cerr << setw(25) << "-input " << adadelta_input << endl;
if (adadelta_output != "")
cerr << setw(25) << "-output " << adadelta_output << endl;
}
cerr << "(1 dot per processed input)" << endl;
// meta
weight_t best=0., gold_prev=0.;
size_t best_iteration = 0;
time_t total_time = 0.;
// output
WriteFile out_up, out_raw;
if (output_raw) {
out_raw.Init(output_raw_fn);
*out_raw << setprecision(numeric_limits<double>::digits10+1);
}
if (output_updates) {
out_up.Init(output_updates_fn);
*out_up << setprecision(numeric_limits<double>::digits10+1);
}
// adadelta
SparseVector<weight_t> gradient_accum, update_accum;
if (use_adadelta && adadelta_input!="") {
vector<weight_t> grads_tmp;
Weights::InitFromFile(adadelta_input+".gradient.gz", &grads_tmp);
Weights::InitSparseVector(grads_tmp, &gradient_accum);
vector<weight_t> update_tmp;
Weights::InitFromFile(adadelta_input+".update.gz", &update_tmp);
Weights::InitSparseVector(update_tmp, &update_accum);
}
for (size_t t = 0; t < T; t++) // T iterations
{
// batch update
SparseVector<weight_t> batch_update;
time_t start, end;
time(&start);
weight_t gold_sum=0., model_sum=0.;
size_t i=0, num_up=0, feature_count=0, list_sz=0;
cerr << "Iteration #" << t+1 << " of " << T << "." << endl;
while(true)
{
bool next = true;
// getting input
if (t == 0) {
string in;
if(!getline(*input, in)) {
next = false;
} else {
vector<string> parts;
boost::algorithm::split_regex(parts, in, boost::regex(" \\|\\|\\| "));
buf.push_back(parts[0]);
parts.erase(parts.begin());
buffered_ngrams.push_back({});
buffered_lengths.push_back({});
for (auto s: parts) {
vector<WordID> r;
vector<string> toks;
boost::split(toks, s, boost::is_any_of(" "));
for (auto tok: toks)
r.push_back(TD::Convert(tok));
buffered_ngrams.back().emplace_back(ngrams(r, N));
buffered_lengths.back().push_back(r.size());
}
}
} else {
next = i<input_sz;
}
if (max_input == i)
next = false;
// produce some pretty output
if (next) {
if (i%20 == 0)
cerr << " ";
cerr << ".";
if ((i+1)%20==0)
cerr << " " << i+1 << endl;
} else {
if (i%20 != 0)
cerr << " " << i << endl;
}
cerr.flush();
// stop iterating
if (!next) break;
// decode
if (t > 0 || i > 0)
lambdas.init_vector(&decoder_weights);
observer->reference_ngrams = &buffered_ngrams[i];
observer->reference_lengths = &buffered_lengths[i];
decoder.Decode(buf[i], observer);
vector<Hyp>* sample = &(observer->sample);
// stats for 1-best
gold_sum += sample->front().gold;
model_sum += sample->front().model;
feature_count += observer->feature_count;
list_sz += observer->effective_size;
if (output_raw)
output_sample(sample, out_raw, i);
// update model
if (!noup) {
SparseVector<weight_t> updates;
if (structured)
num_up += update_structured(sample, updates, margin,
out_up, i);
else if (all_pairs)
num_up += updates_all(sample, updates, max_up, threshold,
out_up, i);
else if (pro)
num_up += updates_pro(sample, updates, cut, max_up, threshold,
out_up, i);
else
num_up += updates_multipartite(sample, updates, cut, margin,
max_up, threshold, adjust_cut,
out_up, i);
SparseVector<weight_t> lambdas_copy;
if (l1_reg)
lambdas_copy = lambdas;
if (use_adadelta) { // adadelta update
SparseVector<weight_t> squared;
for (auto it: updates)
squared[it.first] = pow(it.second, 2.0);
gradient_accum *= adadelta_decay;
squared *= 1.0-adadelta_decay;
gradient_accum += squared;
SparseVector<weight_t> u = gradient_accum + update_accum;
for (auto it: u)
u[it.first] = -1.0*(
sqrt(update_accum[it.first]+adadelta_eta)
/
sqrt(gradient_accum[it.first]+adadelta_eta)
) * updates[it.first];
lambdas += u;
update_accum *= adadelta_decay;
for (auto it: u)
u[it.first] = pow(it.second, 2.0);
update_accum = update_accum + (u*(1.0-adadelta_decay));
} else if (batch) {
batch_update += updates;
} else { // regular update
lambdas.plus_eq_v_times_s(updates, eta);
}
// update context for Chiang's approx. BLEU
if (score_name == "chiang") {
for (auto it: *sample) {
if (it.rank == 0) {
scorer->update_context(it.w, buffered_ngrams[i],
buffered_lengths[i], chiang_decay);
break;
}
}
}
// \ell_1 regularization
// NB: regularization is done after each sentence,
// not after every single pair!
if (l1_reg) {
SparseVector<weight_t>::iterator it = lambdas.begin();
for (; it != lambdas.end(); ++it) {
weight_t v = it->second;
if (!v)
continue;
if (!lambdas_copy.get(it->first) // new or..
|| lambdas_copy.get(it->first)!=v) // updated feature
{
if (v > 0) {
it->second = max(0., v - l1_reg);
} else {
it->second = min(0., v + l1_reg);
}
}
}
}
} // noup
i++;
} // input loop
if (t == 0)
input_sz = i; // remember size of input (# lines)
// batch
if (batch) {
batch_update /= (weight_t)num_up;
lambdas.plus_eq_v_times_s(batch_update, eta);
lambdas.init_vector(&decoder_weights);
}
// update average
if (average)
w_average += lambdas;
if (adadelta_output != "") {
WriteFile g(adadelta_output+".gradient.gz");
for (auto it: gradient_accum)
*g << FD::Convert(it.first) << " " << it.second << endl;
WriteFile u(adadelta_output+".update.gz");
for (auto it: update_accum)
*u << FD::Convert(it.first) << " " << it.second << endl;
}
// stats
weight_t gold_avg = gold_sum/(weight_t)input_sz;
cerr << setiosflags(ios::showpos) << scientific << "WEIGHTS" << endl;
for (auto name: print_weights) {
cerr << setw(18) << name << " = "
<< lambdas.get(FD::Convert(name));
if (use_adadelta) {
weight_t rate = -1.0*(sqrt(update_accum[FD::Convert(name)]+adadelta_eta)
/ sqrt(gradient_accum[FD::Convert(name)]+adadelta_eta));
cerr << " {" << rate << "}";
}
cerr << endl;
}
cerr << " ---" << endl;
cerr << resetiosflags(ios::showpos)
<< " 1best avg score: " << gold_avg*100;
cerr << setiosflags(ios::showpos) << fixed << " ("
<< (gold_avg-gold_prev)*100 << ")" << endl;
cerr << scientific << " 1best avg model score: "
<< model_sum/(weight_t)input_sz << endl;
cerr << fixed;
cerr << " avg # updates: ";
cerr << resetiosflags(ios::showpos) << num_up/(float)input_sz << endl;
cerr << " non-0 feature count: " << lambdas.num_nonzero() << endl;
cerr << " avg f count: " << feature_count/(float)list_sz << endl;
cerr << " avg list sz: " << list_sz/(float)input_sz << endl;
if (gold_avg > best) {
best = gold_avg;
best_iteration = t;
}
gold_prev = gold_avg;
time (&end);
time_t time_diff = difftime(end, start);
total_time += time_diff;
cerr << "(time " << time_diff/60. << " min, ";
cerr << time_diff/input_sz << " s/S)" << endl;
if (t+1 != T) cerr << endl;
if (keep) { // keep intermediate weights
lambdas.init_vector(&decoder_weights);
string w_fn = "weights." + boost::lexical_cast<string>(t) + ".gz";
Weights::WriteToFile(w_fn, decoder_weights, true);
}
} // outer loop
// final weights
if (average) {
w_average /= T;
w_average.init_vector(decoder_weights);
} else if (!keep) {
lambdas.init_vector(decoder_weights);
}
if (average || !keep)
Weights::WriteToFile(output_fn, decoder_weights, true);
cerr << endl << "---" << endl << "Best iteration: ";
cerr << best_iteration+1 << " [GOLD = " << best*100 << "]." << endl;
cerr << "This took " << total_time/60. << " min." << endl;
return 0;
}
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