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#include "config.h"
#include <boost/shared_ptr.hpp>
#include <boost/program_options.hpp>
#include <boost/program_options/variables_map.hpp>
#include "filelib.h"
#include "stringlib.h"
#include "weights.h"
#include "sparse_vector.h"
#include "candidate_set.h"
#include "sentence_metadata.h"
#include "ns.h"
#include "ns_docscorer.h"
#include "verbose.h"
#include "hg.h"
#include "ff_register.h"
#include "decoder.h"
#include "fdict.h"
#include "sampler.h"
using namespace std;
namespace po = boost::program_options;
boost::shared_ptr<MT19937> rng;
vector<training::CandidateSet> kbests;
SparseVector<weight_t> G, u, lambdas;
double pseudo_doc_decay = 0.9;
bool InitCommandLine(int argc, char** argv, po::variables_map* conf) {
po::options_description opts("Configuration options");
opts.add_options()
("decoder_config,c",po::value<string>(),"[REQ] Decoder configuration file")
("devset,d",po::value<string>(),"[REQ] Source/reference development set")
("weights,w",po::value<string>(),"Initial feature weights file")
("mt_metric,m",po::value<string>()->default_value("ibm_bleu"), "Scoring metric (ibm_bleu, nist_bleu, koehn_bleu, ter, combi)")
("size",po::value<unsigned>()->default_value(0), "Process rank (for multiprocess mode)")
("rank",po::value<unsigned>()->default_value(1), "Number of processes (for multiprocess mode)")
("optimizer,o",po::value<unsigned>()->default_value(1), "Optimizer (Adaptive MIRA=1)")
("fear,f",po::value<unsigned>()->default_value(1), "Fear selection (model-cost=1, maxcost=2, maxscore=3)")
("hope,h",po::value<unsigned>()->default_value(1), "Hope selection (model+cost=1, mincost=2)")
("eta0", po::value<double>()->default_value(0.1), "Initial step size")
("random_seed,S", po::value<uint32_t>(), "Random seed (if not specified, /dev/random will be used)")
("mt_metric_scale,s", po::value<double>()->default_value(1.0), "Scale MT loss function by this amount")
("pseudo_doc,e", "Use pseudo-documents for approximate scoring")
("k_best_size,k", po::value<unsigned>()->default_value(500), "Size of hypothesis list to search for oracles");
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("decoder_config")
|| !conf->count("devset")) {
cerr << dcmdline_options << endl;
return false;
}
return true;
}
struct TrainingObserver : public DecoderObserver {
explicit TrainingObserver(const EvaluationMetric& m, const int k) : metric(m), kbest_size(k), cur_eval() {}
const EvaluationMetric& metric;
const int kbest_size;
const SegmentEvaluator* cur_eval;
SufficientStats pdoc;
unsigned hi, vi, fi; // hope, viterbi, fear
void SetSegmentEvaluator(const SegmentEvaluator* eval) {
cur_eval = eval;
}
virtual void NotifySourceParseFailure(const SentenceMetadata& smeta) {
cerr << "Failed to translate sentence with ID = " << smeta.GetSentenceID() << endl;
abort();
}
unsigned CostAugmentedDecode(const training::CandidateSet& cs,
const SparseVector<double>& w,
double alpha = 0) {
unsigned best_i = 0;
double best = -numeric_limits<double>::infinity();
for (unsigned i = 0; i < cs.size(); ++i) {
double s = cs[i].fmap.dot(w);
if (alpha)
s += alpha * metric.ComputeScore(cs[i].eval_feats + pdoc);
if (s > best) {
best = s;
best_i = i;
}
}
return best_i;
}
virtual void NotifyTranslationForest(const SentenceMetadata& smeta, Hypergraph* hg) {
pdoc *= pseudo_doc_decay;
const unsigned sent_id = smeta.GetSentenceID();
kbests[sent_id].AddUniqueKBestCandidates(*hg, kbest_size, cur_eval);
vi = CostAugmentedDecode(kbests[sent_id], lambdas);
hi = CostAugmentedDecode(kbests[sent_id], lambdas, 1.0);
fi = CostAugmentedDecode(kbests[sent_id], lambdas, -1.0);
cerr << sent_id << " ||| " << TD::GetString(kbests[sent_id][vi].ewords) << " ||| " << metric.ComputeScore(kbests[sent_id][vi].eval_feats + pdoc) << endl;
pdoc += kbests[sent_id][vi].eval_feats; // update pseudodoc stats
}
};
int main(int argc, char** argv) {
SetSilent(true); // turn off verbose decoder output
register_feature_functions();
po::variables_map conf;
if (!InitCommandLine(argc, argv, &conf)) return 1;
if (conf.count("random_seed"))
rng.reset(new MT19937(conf["random_seed"].as<uint32_t>()));
else
rng.reset(new MT19937);
string metric_name = UppercaseString(conf["mt_metric"].as<string>());
if (metric_name == "COMBI") {
cerr << "WARNING: 'combi' metric is no longer supported, switching to 'COMB:TER=-0.5;IBM_BLEU=0.5'\n";
metric_name = "COMB:TER=-0.5;IBM_BLEU=0.5";
} else if (metric_name == "BLEU") {
cerr << "WARNING: 'BLEU' is ambiguous, assuming 'IBM_BLEU'\n";
metric_name = "IBM_BLEU";
}
EvaluationMetric* metric = EvaluationMetric::Instance(metric_name);
DocumentScorer ds(metric, conf["devset"].as<string>());
cerr << "Loaded " << ds.size() << " references for scoring with " << metric_name << endl;
kbests.resize(ds.size());
double eta = 0.001;
ReadFile ini_rf(conf["decoder_config"].as<string>());
Decoder decoder(ini_rf.stream());
vector<weight_t>& dense_weights = decoder.CurrentWeightVector();
if (conf.count("weights")) {
Weights::InitFromFile(conf["weights"].as<string>(), &dense_weights);
Weights::InitSparseVector(dense_weights, &lambdas);
}
TrainingObserver observer(*metric, conf["k_best_size"].as<unsigned>());
unsigned num = 200;
for (unsigned iter = 1; iter < num; ++iter) {
lambdas.init_vector(&dense_weights);
unsigned sent_id = rng->next() * ds.size();
cerr << "Learning from sentence id: " << sent_id << endl;
observer.SetSegmentEvaluator(ds[sent_id]);
decoder.SetId(sent_id);
decoder.Decode(ds[sent_id]->src, &observer);
if (observer.vi != observer.hi) { // viterbi != hope
SparseVector<double> grad = kbests[sent_id][observer.fi].fmap;
grad -= kbests[sent_id][observer.hi].fmap;
cerr << "GRAD: " << grad << endl;
const SparseVector<double>& g = grad;
#if HAVE_CXX11 && (__GNUC_MINOR__ > 4 || __GNUC__ > 4)
for (auto& gi : g) {
#else
for (SparseVector<double>::const_iterator it = g.begin(); it != g.end(); ++it) {
const pair<unsigned,double>& gi = *it;
#endif
if (gi.second) {
u[gi.first] += gi.second;
G[gi.first] += gi.second * gi.second;
lambdas.set_value(gi.first, 1.0); // this is a dummy value to trigger recomputation
}
}
for (SparseVector<double>::iterator it = lambdas.begin(); it != lambdas.end(); ++it) {
const pair<unsigned,double>& xi = *it;
double z = fabs(u[xi.first] / iter) - 0.0;
double s = 1;
if (u[xi.first] > 0) s = -1;
if (z > 0 && G[xi.first]) {
lambdas.set_value(xi.first, eta * s * z * iter / sqrt(G[xi.first]));
} else {
lambdas.set_value(xi.first, 0.0);
}
}
}
}
cerr << "Optimization complete.\n";
Weights::WriteToFile("-", dense_weights, true);
return 0;
}
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