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/*
* Featurize a grammar in striped format
*/
#include <iostream>
#include <string>
#include <map>
#include <vector>
#include <utility>
#include <cstdlib>
#include <fstream>
#include <tr1/unordered_map>
#include "suffix_tree.h"
#include "sparse_vector.h"
#include "sentence_pair.h"
#include "extract.h"
#include "fdict.h"
#include "tdict.h"
#include "lex_trans_tbl.h"
#include "filelib.h"
#include <boost/shared_ptr.hpp>
#include <boost/functional/hash.hpp>
#include <boost/program_options.hpp>
#include <boost/program_options/variables_map.hpp>
using namespace std;
using namespace std::tr1;
namespace po = boost::program_options;
static const size_t MAX_LINE_LENGTH = 64000000;
typedef unordered_map<vector<WordID>, RuleStatistics, boost::hash<vector<WordID> > > ID2RuleStatistics;
void InitCommandLine(int argc, char** argv, po::variables_map* conf) {
po::options_description opts("Configuration options");
opts.add_options()
("filtered_grammar,g", po::value<string>(), "Grammar to add features to")
("aligned_corpus,c", po::value<string>(), "Aligned corpus (single line format)")
("help,h", "Print this help message and exit");
po::options_description clo("Command line options");
po::options_description dcmdline_options;
dcmdline_options.add(opts);
po::store(parse_command_line(argc, argv, dcmdline_options), *conf);
po::notify(*conf);
if (conf->count("help") || conf->count("aligned_corpus")==0) {
cerr << "\nUsage: featurize_grammar -g FILTERED-GRAMMAR.gz -c ALIGNED_CORPUS.fr-en-al [-options] < UNFILTERED-GRAMMAR\n";
cerr << dcmdline_options << endl;
exit(1);
}
}
namespace {
inline bool IsWhitespace(char c) { return c == ' ' || c == '\t'; }
inline bool IsBracket(char c){return c == '[' || c == ']';}
inline void SkipWhitespace(const char* buf, int* ptr) {
while (buf[*ptr] && IsWhitespace(buf[*ptr])) { ++(*ptr); }
}
}
int ReadPhraseUntilDividerOrEnd(const char* buf, const int sstart, const int end, vector<WordID>* p) {
static const WordID kDIV = TD::Convert("|||");
int ptr = sstart;
while(ptr < end) {
while(ptr < end && IsWhitespace(buf[ptr])) { ++ptr; }
int start = ptr;
while(ptr < end && !IsWhitespace(buf[ptr])) { ++ptr; }
if (ptr == start) {cerr << "Warning! empty token.\n"; return ptr; }
const WordID w = TD::Convert(string(buf, start, ptr - start));
if((IsBracket(buf[start]) and IsBracket(buf[ptr-1])) or( w == kDIV))
p->push_back(1 * w);
else {
if (w == kDIV) return ptr;
p->push_back(w);
}
}
return ptr;
}
void ParseLine(const char* buf, vector<WordID>* cur_key, ID2RuleStatistics* counts) {
static const WordID kDIV = TD::Convert("|||");
counts->clear();
int ptr = 0;
while(buf[ptr] != 0 && buf[ptr] != '\t') { ++ptr; }
if (buf[ptr] != '\t') {
cerr << "Missing tab separator between key and value!\n INPUT=" << buf << endl;
exit(1);
}
cur_key->clear();
// key is: "[X] ||| word word word"
int tmpp = ReadPhraseUntilDividerOrEnd(buf, 0, ptr, cur_key);
cur_key->push_back(kDIV);
ReadPhraseUntilDividerOrEnd(buf, tmpp, ptr, cur_key);
++ptr;
int start = ptr;
int end = ptr;
int state = 0; // 0=reading label, 1=reading count
vector<WordID> name;
while(buf[ptr] != 0) {
while(buf[ptr] != 0 && buf[ptr] != '|') { ++ptr; }
if (buf[ptr] == '|') {
++ptr;
if (buf[ptr] == '|') {
++ptr;
if (buf[ptr] == '|') {
++ptr;
end = ptr - 3;
while (end > start && IsWhitespace(buf[end-1])) { --end; }
if (start == end) {
cerr << "Got empty token!\n LINE=" << buf << endl;
exit(1);
}
switch (state) {
case 0: ++state; name.clear(); ReadPhraseUntilDividerOrEnd(buf, start, end, &name); break;
case 1: --state; (*counts)[name].ParseRuleStatistics(buf, start, end); break;
default: cerr << "Can't happen\n"; abort();
}
SkipWhitespace(buf, &ptr);
start = ptr;
}
}
}
}
end=ptr;
while (end > start && IsWhitespace(buf[end-1])) { --end; }
if (end > start) {
switch (state) {
case 0: ++state; name.clear(); ReadPhraseUntilDividerOrEnd(buf, start, end, &name); break;
case 1: --state; (*counts)[name].ParseRuleStatistics(buf, start, end); break;
default: cerr << "Can't happen\n"; abort();
}
}
}
void LexTranslationTable::createTTable(const char* buf){
AnnotatedParallelSentence sent;
sent.ParseInputLine(buf);
//iterate over the alignment to compute aligned words
for(int i =0;i<sent.aligned.width();i++)
{
for (int j=0;j<sent.aligned.height();j++)
{
if (DEBUG) cerr << sent.aligned(i,j) << " ";
if( sent.aligned(i,j))
{
if (DEBUG) cerr << TD::Convert(sent.f[i]) << " aligned to " << TD::Convert(sent.e[j]);
++word_translation[pair<WordID,WordID> (sent.f[i], sent.e[j])];
++total_foreign[sent.f[i]];
++total_english[sent.e[j]];
}
}
if (DEBUG) cerr << endl;
}
if (DEBUG) cerr << endl;
const WordID NULL_ = TD::Convert("NULL");
//handle unaligned words - align them to null
for (int j =0; j < sent.e_len; j++) {
if (sent.e_aligned[j]) continue;
++word_translation[pair<WordID,WordID> (NULL_, sent.e[j])];
++total_foreign[NULL_];
++total_english[sent.e[j]];
}
for (int i =0; i < sent.f_len; i++) {
if (sent.f_aligned[i]) continue;
++word_translation[pair<WordID,WordID> (sent.f[i], NULL_)];
++total_english[NULL_];
++total_foreign[sent.f[i]];
}
}
inline float safenlog(float v) {
if (v == 1.0f) return 0.0f;
float res = -log(v);
if (res > 100.0f) res = 100.0f;
return res;
}
static bool IsZero(float f) { return (f > 0.999 && f < 1.001); }
struct FeatureExtractor {
// create any keys necessary
virtual void ObserveFilteredRule(const WordID lhs,
const vector<WordID>& src,
const vector<WordID>& trg) {}
// compute statistics over keys, the same lhs-src-trg tuple may be seen
// more than once
virtual void ObserveUnfilteredRule(const WordID lhs,
const vector<WordID>& src,
const vector<WordID>& trg,
const RuleStatistics& info) {}
// compute features, a unique lhs-src-trg tuple will be seen exactly once
virtual void ExtractFeatures(const WordID lhs,
const vector<WordID>& src,
const vector<WordID>& trg,
const RuleStatistics& info,
SparseVector<float>* result) const = 0;
virtual ~FeatureExtractor() {}
};
struct LogRuleCount : public FeatureExtractor {
LogRuleCount() :
fid_(FD::Convert("LogRuleCount")),
sfid_(FD::Convert("SingletonRule")),
kCFE(FD::Convert("CFE")) {}
virtual void ExtractFeatures(const WordID lhs,
const vector<WordID>& src,
const vector<WordID>& trg,
const RuleStatistics& info,
SparseVector<float>* result) const {
(void) lhs; (void) src; (void) trg;
result->set_value(fid_, log(info.counts.value(kCFE)));
if (IsZero(info.counts.value(kCFE)))
result->set_value(sfid_, 1);
}
const int fid_;
const int sfid_;
const int kCFE;
};
// this extracts the lexical translation prob features
// in BOTH directions.
struct LexProbExtractor : public FeatureExtractor {
LexProbExtractor(const std::string& corpus) :
e2f_(FD::Convert("LexE2F")), f2e_(FD::Convert("LexF2E")) {
ReadFile rf(corpus);
//create lexical translation table
cerr << "Computing lexical translation probabilities from " << corpus << "..." << endl;
char* buf = new char[MAX_LINE_LENGTH];
istream& alignment = *rf.stream();
while(alignment) {
alignment.getline(buf, MAX_LINE_LENGTH);
if (buf[0] == 0) continue;
table.createTTable(buf);
}
delete[] buf;
}
virtual void ExtractFeatures(const WordID lhs,
const vector<WordID>& src,
const vector<WordID>& trg,
const RuleStatistics& info,
SparseVector<float>* result) const {
map <WordID, pair<int, float> > foreign_aligned;
map <WordID, pair<int, float> > english_aligned;
//Loop over all the alignment points to compute lexical translation probability
const vector< pair<short,short> >& al = info.aligns;
vector< pair<short,short> >::const_iterator ita;
for (ita = al.begin(); ita != al.end(); ++ita) {
if (DEBUG) {
cerr << "\nA:" << ita->first << "," << ita->second << "::";
cerr << TD::Convert(src[ita->first]) << "-" << TD::Convert(trg[ita->second]);
}
//Lookup this alignment probability in the table
int temp = table.word_translation[pair<WordID,WordID> (src[ita->first],trg[ita->second])];
float f2e=0, e2f=0;
if ( table.total_foreign[src[ita->first]] != 0)
f2e = (float) temp / table.total_foreign[src[ita->first]];
if ( table.total_english[trg[ita->second]] !=0 )
e2f = (float) temp / table.total_english[trg[ita->second]];
if (DEBUG) printf (" %d %E %E\n", temp, f2e, e2f);
//local counts to keep track of which things haven't been aligned, to later compute their null alignment
if (foreign_aligned.count(src[ita->first])) {
foreign_aligned[ src[ita->first] ].first++;
foreign_aligned[ src[ita->first] ].second += e2f;
} else {
foreign_aligned[ src[ita->first] ] = pair<int,float> (1,e2f);
}
if (english_aligned.count( trg[ ita->second] )) {
english_aligned[ trg[ ita->second] ].first++;
english_aligned[ trg[ ita->second] ].second += f2e;
} else {
english_aligned[ trg[ ita->second] ] = pair<int,float> (1,f2e);
}
}
float final_lex_f2e=1, final_lex_e2f=1;
static const WordID NULL_ = TD::Convert("NULL");
//compute lexical weight P(F|E) and include unaligned foreign words
for(int i=0;i<src.size(); i++) {
if (!table.total_foreign.count(src[i])) continue; //if we dont have it in the translation table, we won't know its lexical weight
if (foreign_aligned.count(src[i]))
{
pair<int, float> temp_lex_prob = foreign_aligned[src[i]];
final_lex_e2f *= temp_lex_prob.second / temp_lex_prob.first;
}
else //dealing with null alignment
{
int temp_count = table.word_translation[pair<WordID,WordID> (src[i],NULL_)];
float temp_e2f = (float) temp_count / table.total_english[NULL_];
final_lex_e2f *= temp_e2f;
}
}
//compute P(E|F) unaligned english words
for(int j=0; j< trg.size(); j++) {
if (!table.total_english.count(trg[j])) continue;
if (english_aligned.count(trg[j]))
{
pair<int, float> temp_lex_prob = english_aligned[trg[j]];
final_lex_f2e *= temp_lex_prob.second / temp_lex_prob.first;
}
else //dealing with null
{
int temp_count = table.word_translation[pair<WordID,WordID> (NULL_,trg[j])];
float temp_f2e = (float) temp_count / table.total_foreign[NULL_];
final_lex_f2e *= temp_f2e;
}
}
result->set_value(e2f_, safenlog(final_lex_e2f));
result->set_value(f2e_, safenlog(final_lex_f2e));
}
const int e2f_, f2e_;
mutable LexTranslationTable table;
};
int main(int argc, char** argv){
po::variables_map conf;
InitCommandLine(argc, argv, &conf);
ifstream alignment (conf["aligned_corpus"].as<string>().c_str());
ReadFile fg1(conf["filtered_grammar"].as<string>());
istream& fs1 = *fg1.stream();
// TODO make this list configurable
vector<boost::shared_ptr<FeatureExtractor> > extractors;
extractors.push_back(boost::shared_ptr<FeatureExtractor>(new LogRuleCount));
extractors.push_back(boost::shared_ptr<FeatureExtractor>(new LexProbExtractor(conf["aligned_corpus"].as<string>())));
//score unscored grammar
cerr << "Reading filtered grammar to detect keys..." << endl;
char* buf = new char[MAX_LINE_LENGTH];
ID2RuleStatistics acc, cur_counts;
vector<WordID> key, cur_key,temp_key;
WordID lhs = 0;
vector<WordID> src;
#if 0
int line = 0;
while(fs1) {
fs1.getline(buf, MAX_LINE_LENGTH);
if (buf[0] == 0) continue;
ParseLine(buf, &cur_key, &cur_counts);
src.resize(cur_key.size() - 2);
for (int i = 0; i < src.size(); ++i) src[i] = cur_key[i+2];
lhs = cur_key[0];
for (ID2RuleStatistics::const_iterator it = cur_counts.begin(); it != cur_counts.end(); ++it) {
for (int i = 0; i < extractors.size(); ++i)
extractors[i]->ObserveFilteredRule(lhs, src, it->first);
}
}
cerr << "Reading unfiltered grammar..." << endl;
while(cin) {
cin.getline(buf, MAX_LINE_LENGTH);
if (buf[0] == 0) continue;
ParseLine(buf, &cur_key, &cur_counts);
src.resize(cur_key.size() - 2);
for (int i = 0; i < src.size(); ++i) src[i] = cur_key[i+2];
lhs = cur_key[0];
for (ID2RuleStatistics::const_iterator it = cur_counts.begin(); it != cur_counts.end(); ++it) {
// TODO set lhs, src, trg
for (int i = 0; i < extractors.size(); ++i)
extractors[i]->ObserveUnfilteredRule(lhs, src, it->first, it->second);
}
}
#endif
ReadFile fg2(conf["filtered_grammar"].as<string>());
istream& fs2 = *fg2.stream();
cerr << "Reading filtered grammar and adding features..." << endl;
while(fs2) {
fs2.getline(buf, MAX_LINE_LENGTH);
if (buf[0] == 0) continue;
ParseLine(buf, &cur_key, &cur_counts);
src.resize(cur_key.size() - 2);
for (int i = 0; i < src.size(); ++i) src[i] = cur_key[i+2];
lhs = cur_key[0];
//loop over all the Target side phrases that this source aligns to
for (ID2RuleStatistics::const_iterator it = cur_counts.begin(); it != cur_counts.end(); ++it) {
SparseVector<float> feats;
for (int i = 0; i < extractors.size(); ++i)
extractors[i]->ExtractFeatures(lhs, src, it->first, it->second, &feats);
cout << TD::GetString(cur_key) << " ||| " << TD::GetString(it->first) << " ||| ";
feats.Write(false, &cout);
cout << endl;
}
}
}
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