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#ifndef _TTABLES_H_
#define _TTABLES_H_
#include <iostream>
#include <tr1/unordered_map>
#include "wordid.h"
#include "tdict.h"
#include "em_utils.h"
class TTable {
public:
TTable() {}
typedef std::tr1::unordered_map<WordID, double> Word2Double;
typedef std::tr1::unordered_map<WordID, Word2Double> Word2Word2Double;
inline double prob(const int& e, const int& f) const {
const Word2Word2Double::const_iterator cit = ttable.find(e);
if (cit != ttable.end()) {
const Word2Double& cpd = cit->second;
const Word2Double::const_iterator it = cpd.find(f);
if (it == cpd.end()) return 1e-9;
return it->second;
} else {
return 1e-9;
}
}
inline void Increment(const int& e, const int& f) {
counts[e][f] += 1.0;
}
inline void Increment(const int& e, const int& f, double x) {
counts[e][f] += x;
}
void NormalizeVB(const double alpha) {
ttable.swap(counts);
for (Word2Word2Double::iterator cit = ttable.begin();
cit != ttable.end(); ++cit) {
double tot = 0;
Word2Double& cpd = cit->second;
for (Word2Double::iterator it = cpd.begin(); it != cpd.end(); ++it)
tot += it->second + alpha;
for (Word2Double::iterator it = cpd.begin(); it != cpd.end(); ++it)
it->second = exp(digamma(it->second + alpha) - digamma(tot));
}
counts.clear();
}
void Normalize() {
ttable.swap(counts);
for (Word2Word2Double::iterator cit = ttable.begin();
cit != ttable.end(); ++cit) {
double tot = 0;
Word2Double& cpd = cit->second;
for (Word2Double::iterator it = cpd.begin(); it != cpd.end(); ++it)
tot += it->second;
for (Word2Double::iterator it = cpd.begin(); it != cpd.end(); ++it)
it->second /= tot;
}
counts.clear();
}
// adds counts from another TTable - probabilities remain unchanged
TTable& operator+=(const TTable& rhs) {
for (Word2Word2Double::const_iterator it = rhs.counts.begin();
it != rhs.counts.end(); ++it) {
const Word2Double& cpd = it->second;
Word2Double& tgt = counts[it->first];
for (Word2Double::const_iterator j = cpd.begin(); j != cpd.end(); ++j) {
tgt[j->first] += j->second;
}
}
return *this;
}
void ShowTTable() {
for (Word2Word2Double::iterator it = ttable.begin(); it != ttable.end(); ++it) {
Word2Double& cpd = it->second;
for (Word2Double::iterator j = cpd.begin(); j != cpd.end(); ++j) {
std::cerr << "P(" << TD::Convert(j->first) << '|' << TD::Convert(it->first) << ") = " << j->second << std::endl;
}
}
}
void ShowCounts() {
for (Word2Word2Double::iterator it = counts.begin(); it != counts.end(); ++it) {
Word2Double& cpd = it->second;
for (Word2Double::iterator j = cpd.begin(); j != cpd.end(); ++j) {
std::cerr << "c(" << TD::Convert(j->first) << '|' << TD::Convert(it->first) << ") = " << j->second << std::endl;
}
}
}
void DeserializeProbsFromText(std::istream* in);
void SerializeCounts(std::string* out) const { SerializeHelper(out, counts); }
void DeserializeCounts(const std::string& in) { DeserializeHelper(in, &counts); }
void SerializeProbs(std::string* out) const { SerializeHelper(out, ttable); }
void DeserializeProbs(const std::string& in) { DeserializeHelper(in, &ttable); }
private:
static void SerializeHelper(std::string*, const Word2Word2Double& o);
static void DeserializeHelper(const std::string&, Word2Word2Double* o);
public:
Word2Word2Double ttable;
Word2Word2Double counts;
};
#endif
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