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#include <iostream>
#include <tr1/memory>
#include <queue>
#include <boost/multi_array.hpp>
#include <boost/program_options.hpp>
#include <boost/program_options/variables_map.hpp>
#include "backward.h"
#include "array2d.h"
#include "base_distributions.h"
#include "monotonic_pseg.h"
#include "conditional_pseg.h"
#include "trule.h"
#include "tdict.h"
#include "stringlib.h"
#include "filelib.h"
#include "dict.h"
#include "sampler.h"
#include "mfcr.h"
#include "corpus.h"
#include "ngram_base.h"
#include "transliterations.h"
using namespace std;
using namespace tr1;
namespace po = boost::program_options;
void InitCommandLine(int argc, char** argv, po::variables_map* conf) {
po::options_description opts("Configuration options");
opts.add_options()
("samples,s",po::value<unsigned>()->default_value(1000),"Number of samples")
("input,i",po::value<string>(),"Read parallel data from")
("s2t", po::value<string>(), "character level source-to-target prior transliteration probabilities")
("t2s", po::value<string>(), "character level target-to-source prior transliteration probabilities")
("max_src_chunk", po::value<unsigned>()->default_value(4), "Maximum size of translitered chunk in source")
("max_trg_chunk", po::value<unsigned>()->default_value(4), "Maximum size of translitered chunk in target")
("expected_src_to_trg_ratio", po::value<double>()->default_value(1.0), "If a word is transliterated, what is the expected length ratio from source to target?")
("random_seed,S",po::value<uint32_t>(), "Random seed");
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 << dcmdline_options << endl;
exit(1);
}
}
boost::shared_ptr<MT19937> prng;
struct LexicalAlignment {
unsigned char src_index;
bool is_transliteration;
vector<pair<short, short> > derivation;
};
struct AlignedSentencePair {
vector<WordID> src;
vector<WordID> trg;
vector<LexicalAlignment> a;
Array2D<short> posterior;
};
struct HierarchicalWordBase {
explicit HierarchicalWordBase(const unsigned vocab_e_size) :
base(prob_t::One()), r(1,1,1,1,0.66,50.0), u0(-log(vocab_e_size)), l(1,prob_t::One()), v(1, prob_t::Zero()) {}
void ResampleHyperparameters(MT19937* rng) {
r.resample_hyperparameters(rng);
}
inline double logp0(const vector<WordID>& s) const {
return Md::log_poisson(s.size(), 7.5) + s.size() * u0;
}
// return p0 of rule.e_
prob_t operator()(const TRule& rule) const {
v[0].logeq(logp0(rule.e_));
return r.prob(rule.e_, v.begin(), l.begin());
}
void Increment(const TRule& rule) {
v[0].logeq(logp0(rule.e_));
if (r.increment(rule.e_, v.begin(), l.begin(), &*prng).count) {
base *= v[0] * l[0];
}
}
void Decrement(const TRule& rule) {
if (r.decrement(rule.e_, &*prng).count) {
base /= prob_t(exp(logp0(rule.e_)));
}
}
prob_t Likelihood() const {
prob_t p; p.logeq(r.log_crp_prob());
p *= base;
return p;
}
void Summary() const {
cerr << "NUMBER OF CUSTOMERS: " << r.num_customers() << " (d=" << r.discount() << ",s=" << r.strength() << ')' << endl;
for (MFCR<1,vector<WordID> >::const_iterator it = r.begin(); it != r.end(); ++it)
cerr << " " << it->second.total_dish_count_ << " (on " << it->second.table_counts_.size() << " tables) " << TD::GetString(it->first) << endl;
}
prob_t base;
MFCR<1,vector<WordID> > r;
const double u0;
const vector<prob_t> l;
mutable vector<prob_t> v;
};
struct BasicLexicalAlignment {
explicit BasicLexicalAlignment(const vector<vector<WordID> >& lets,
const unsigned words_e,
const unsigned letters_e,
vector<AlignedSentencePair>* corp) :
letters(lets),
corpus(*corp),
//up0(words_e),
//up0("en.chars.1gram", letters_e),
//up0("en.words.1gram"),
up0(letters_e),
//up0("en.chars.2gram"),
tmodel(up0) {
}
void InstantiateRule(const WordID src,
const WordID trg,
TRule* rule) const {
static const WordID kX = TD::Convert("X") * -1;
rule->lhs_ = kX;
rule->e_ = letters[trg];
rule->f_ = letters[src];
}
void InitializeRandom() {
const WordID kNULL = TD::Convert("NULL");
cerr << "Initializing with random alignments ...\n";
for (unsigned i = 0; i < corpus.size(); ++i) {
AlignedSentencePair& asp = corpus[i];
asp.a.resize(asp.trg.size());
for (unsigned j = 0; j < asp.trg.size(); ++j) {
const unsigned char a_j = prng->next() * (1 + asp.src.size());
const WordID f_a_j = (a_j ? asp.src[a_j - 1] : kNULL);
TRule r;
InstantiateRule(f_a_j, asp.trg[j], &r);
asp.a[j].is_transliteration = false;
asp.a[j].src_index = a_j;
if (tmodel.IncrementRule(r, &*prng))
up0.Increment(r);
}
}
cerr << " LLH = " << Likelihood() << endl;
}
prob_t Likelihood() const {
prob_t p = tmodel.Likelihood();
p *= up0.Likelihood();
return p;
}
void ResampleHyperparemeters() {
tmodel.ResampleHyperparameters(&*prng);
up0.ResampleHyperparameters(&*prng);
cerr << " (base d=" << up0.r.discount() << ",s=" << up0.r.strength() << ")\n";
}
void ResampleCorpus();
const vector<vector<WordID> >& letters; // spelling dictionary
vector<AlignedSentencePair>& corpus;
//PhraseConditionalUninformativeBase up0;
//PhraseConditionalUninformativeUnigramBase up0;
//UnigramWordBase up0;
//HierarchicalUnigramBase up0;
HierarchicalWordBase up0;
//CompletelyUniformBase up0;
//FixedNgramBase up0;
//ConditionalTranslationModel<PhraseConditionalUninformativeBase> tmodel;
//ConditionalTranslationModel<PhraseConditionalUninformativeUnigramBase> tmodel;
//ConditionalTranslationModel<UnigramWordBase> tmodel;
//ConditionalTranslationModel<HierarchicalUnigramBase> tmodel;
MConditionalTranslationModel<HierarchicalWordBase> tmodel;
//ConditionalTranslationModel<FixedNgramBase> tmodel;
//ConditionalTranslationModel<CompletelyUniformBase> tmodel;
};
void BasicLexicalAlignment::ResampleCorpus() {
static const WordID kNULL = TD::Convert("NULL");
for (unsigned i = 0; i < corpus.size(); ++i) {
AlignedSentencePair& asp = corpus[i];
SampleSet<prob_t> ss; ss.resize(asp.src.size() + 1);
for (unsigned j = 0; j < asp.trg.size(); ++j) {
TRule r;
unsigned char& a_j = asp.a[j].src_index;
WordID f_a_j = (a_j ? asp.src[a_j - 1] : kNULL);
InstantiateRule(f_a_j, asp.trg[j], &r);
if (tmodel.DecrementRule(r, &*prng))
up0.Decrement(r);
for (unsigned prop_a_j = 0; prop_a_j <= asp.src.size(); ++prop_a_j) {
const WordID prop_f = (prop_a_j ? asp.src[prop_a_j - 1] : kNULL);
InstantiateRule(prop_f, asp.trg[j], &r);
ss[prop_a_j] = tmodel.RuleProbability(r);
}
a_j = prng->SelectSample(ss);
f_a_j = (a_j ? asp.src[a_j - 1] : kNULL);
InstantiateRule(f_a_j, asp.trg[j], &r);
if (tmodel.IncrementRule(r, &*prng))
up0.Increment(r);
}
}
cerr << " LLH = " << Likelihood() << endl;
}
void ExtractLetters(const set<WordID>& v, vector<vector<WordID> >* l, set<WordID>* letset = NULL) {
for (set<WordID>::const_iterator it = v.begin(); it != v.end(); ++it) {
vector<WordID>& letters = (*l)[*it];
if (letters.size()) continue; // if e and f have the same word
const string& w = TD::Convert(*it);
size_t cur = 0;
while (cur < w.size()) {
const size_t len = UTF8Len(w[cur]);
letters.push_back(TD::Convert(w.substr(cur, len)));
if (letset) letset->insert(letters.back());
cur += len;
}
}
}
void Debug(const AlignedSentencePair& asp) {
cerr << TD::GetString(asp.src) << endl << TD::GetString(asp.trg) << endl;
Array2D<bool> a(asp.src.size(), asp.trg.size());
for (unsigned j = 0; j < asp.trg.size(); ++j)
if (asp.a[j].src_index) a(asp.a[j].src_index - 1, j) = true;
cerr << a << endl;
}
void AddSample(AlignedSentencePair* asp) {
for (unsigned j = 0; j < asp->trg.size(); ++j)
asp->posterior(asp->a[j].src_index, j)++;
}
void WriteAlignments(const AlignedSentencePair& asp) {
bool first = true;
for (unsigned j = 0; j < asp.trg.size(); ++j) {
int src_index = -1;
int mc = -1;
for (unsigned i = 0; i <= asp.src.size(); ++i) {
if (asp.posterior(i, j) > mc) {
mc = asp.posterior(i, j);
src_index = i;
}
}
if (src_index) {
if (first) first = false; else cout << ' ';
cout << (src_index - 1) << '-' << j;
}
}
cout << endl;
}
int main(int argc, char** argv) {
po::variables_map conf;
InitCommandLine(argc, argv, &conf);
if (conf.count("random_seed"))
prng.reset(new MT19937(conf["random_seed"].as<uint32_t>()));
else
prng.reset(new MT19937);
// MT19937& rng = *prng;
vector<vector<int> > corpuse, corpusf;
set<int> vocabe, vocabf;
corpus::ReadParallelCorpus(conf["input"].as<string>(), &corpusf, &corpuse, &vocabf, &vocabe);
cerr << "f-Corpus size: " << corpusf.size() << " sentences\n";
cerr << "f-Vocabulary size: " << vocabf.size() << " types\n";
cerr << "f-Corpus size: " << corpuse.size() << " sentences\n";
cerr << "f-Vocabulary size: " << vocabe.size() << " types\n";
assert(corpusf.size() == corpuse.size());
vector<AlignedSentencePair> corpus(corpuse.size());
for (unsigned i = 0; i < corpuse.size(); ++i) {
corpus[i].src.swap(corpusf[i]);
corpus[i].trg.swap(corpuse[i]);
corpus[i].posterior.resize(corpus[i].src.size() + 1, corpus[i].trg.size());
}
corpusf.clear(); corpuse.clear();
vocabf.insert(TD::Convert("NULL"));
vector<vector<WordID> > letters(TD::NumWords() + 1);
set<WordID> letset;
ExtractLetters(vocabe, &letters, &letset);
ExtractLetters(vocabf, &letters, NULL);
letters[TD::Convert("NULL")].clear();
// TODO configure this
const int max_src_chunk = conf["max_src_chunk"].as<unsigned>();
const int max_trg_chunk = conf["max_trg_chunk"].as<unsigned>();
const double s2t_rat = conf["expected_src_to_trg_ratio"].as<double>();
const BackwardEstimator be(conf["s2t"].as<string>(), conf["t2s"].as<string>());
Transliterations tl(max_src_chunk, max_trg_chunk, s2t_rat, be);
cerr << "Initializing transliteration graph structures ...\n";
for (int i = 0; i < corpus.size(); ++i) {
const vector<int>& src = corpus[i].src;
const vector<int>& trg = corpus[i].trg;
for (int j = 0; j < src.size(); ++j) {
const vector<int>& src_let = letters[src[j]];
for (int k = 0; k < trg.size(); ++k) {
const vector<int>& trg_let = letters[trg[k]];
tl.Initialize(src[j], src_let, trg[k], trg_let);
//if (src_let.size() < min_trans_src)
// tl.Forbid(src[j], src_let, trg[k], trg_let);
}
}
}
cerr << endl;
tl.GraphSummary();
return 0;
}
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