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/*
* Score a grammar in striped format
* ./score_grammar <alignment> < filtered.grammar > scored.grammar
*/
#include <iostream>
#include <string>
#include <map>
#include <vector>
#include <utility>
#include <cstdlib>
#include <fstream>
#include <tr1/unordered_map>
#include "sentence_pair.h"
#include "extract.h"
#include "fdict.h"
#include "tdict.h"
#include "lex_trans_tbl.h"
#include "filelib.h"
#include <boost/functional/hash.hpp>
#include <boost/program_options.hpp>
#include <boost/program_options/variables_map.hpp>
using namespace std;
using namespace std::tr1;
static const size_t MAX_LINE_LENGTH = 64000000;
typedef unordered_map<vector<WordID>, RuleStatistics, boost::hash<vector<WordID> > > ID2RuleStatistics;
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){
bool DEBUG = false;
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;
static 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;
}
int main(int argc, char** argv){
bool DEBUG= false;
if (argc != 2) {
cerr << "Usage: " << argv[0] << " corpus.al < filtered.grammar\n";
return 1;
}
ifstream alignment (argv[1]);
istream& unscored_grammar = cin;
ostream& scored_grammar = cout;
//create lexical translation table
cerr << "Creating table..." << endl;
char* buf = new char[MAX_LINE_LENGTH];
LexTranslationTable table;
while(!alignment.eof())
{
alignment.getline(buf, MAX_LINE_LENGTH);
if (buf[0] == 0) continue;
table.createTTable(buf);
}
bool PRINT_TABLE=false;
if (PRINT_TABLE)
{
ofstream trans_table;
trans_table.open("lex_trans_table.out");
for(map < pair<WordID,WordID>,int >::iterator it = table.word_translation.begin(); it != table.word_translation.end(); ++it)
{
trans_table << TD::Convert(it->first.first) << "|||" << TD::Convert(it->first.second) << "==" << it->second << "//" << table.total_foreign[it->first.first] << "//" << table.total_english[it->first.second] << endl;
}
trans_table.close();
}
//score unscored grammar
cerr <<"Scoring grammar..." << endl;
ID2RuleStatistics acc, cur_counts;
vector<WordID> key, cur_key,temp_key;
vector< pair<short,short> > al;
vector< pair<short,short> >::iterator ita;
int line = 0;
static const int kCF = FD::Convert("CF");
static const int kCE = FD::Convert("CE");
static const int kCFE = FD::Convert("CFE");
while(!unscored_grammar.eof())
{
++line;
unscored_grammar.getline(buf, MAX_LINE_LENGTH);
if (buf[0] == 0) continue;
ParseLine(buf, &cur_key, &cur_counts);
//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)
{
/*Compute phrase translation prob.
Print out scores in this format:
Phrase trnaslation prob P(F|E)
Phrase translation prob P(E|F)
Lexical weighting prob lex(F|E)
Lexical weighting prob lex(E|F)
*/
float pEF_ = it->second.counts.value(kCFE) / it->second.counts.value(kCF);
float pFE_ = it->second.counts.value(kCFE) / it->second.counts.value(kCE);
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
al = it->second.aligns;
for(ita = al.begin(); ita != al.end(); ++ita)
{
if (DEBUG)
{
cerr << "\nA:" << ita->first << "," << ita->second << "::";
cerr << TD::Convert(cur_key[ita->first + 2]) << "-" << TD::Convert(it->first[ita->second]);
}
//Lookup this alignment probability in the table
int temp = table.word_translation[pair<WordID,WordID> (cur_key[ita->first+2],it->first[ita->second])];
float f2e=0, e2f=0;
if ( table.total_foreign[cur_key[ita->first+2]] != 0)
f2e = (float) temp / table.total_foreign[cur_key[ita->first+2]];
if ( table.total_english[it->first[ita->second]] !=0 )
e2f = (float) temp / table.total_english[it->first[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(cur_key[ita->first+2]))
{
foreign_aligned[ cur_key[ita->first+2] ].first++;
foreign_aligned[ cur_key[ita->first+2] ].second += e2f;
}
else
foreign_aligned [ cur_key[ita->first+2] ] = pair<int,float> (1,e2f);
if (english_aligned.count( it->first[ ita->second] ))
{
english_aligned[ it->first[ ita->second ]].first++;
english_aligned[ it->first[ ita->second] ].second += f2e;
}
else
english_aligned [ it->first[ 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<cur_key.size(); i++)
{
if (!table.total_foreign.count(cur_key[i])) continue; //if we dont have it in the translation table, we won't know its lexical weight
if (foreign_aligned.count(cur_key[i]))
{
pair<int, float> temp_lex_prob = foreign_aligned[cur_key[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> (cur_key[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< it->first.size(); j++)
{
if (!table.total_english.count(it->first[j])) continue;
if (english_aligned.count(it->first[j]))
{
pair<int, float> temp_lex_prob = english_aligned[it->first[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_,it->first[j])];
float temp_f2e = (float) temp_count / table.total_foreign[NULL_];
final_lex_f2e *= temp_f2e;
}
}
scored_grammar << TD::GetString(cur_key);
string lhs = TD::Convert(cur_key[0]);
scored_grammar << " " << TD::GetString(it->first) << " |||";
if(lhs.find('_')!=string::npos) {
scored_grammar << " Bkoff=" << safenlog(3.0f);
} else {
scored_grammar << " FGivenE=" << safenlog(pFE_) << " EGivenF=" << safenlog(pEF_);
scored_grammar << " LexE2F=" << safenlog(final_lex_e2f) << " LexF2E=" << safenlog(final_lex_f2e);
}
scored_grammar << endl;
}
}
}
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