mosesdecoder/moses/src/DynSAInclude/vocab.cpp

#include <sstream>
#include "vocab.h"

namespace Moses {

	// Vocab class
	void Vocab::InitSpecialWords() 
	{
                m_kBOSWord = InitSpecialWord(BOS_);	// BOS_ is a string <s> (defined in ../typedef.h)
                m_kEOSWord = InitSpecialWord(EOS_);	// EOS_ is a string </s> (defined in ../typedef.h)
                m_kOOVWord = InitSpecialWord(UNKNOWN_FACTOR);	// UNKNOWN_FACTOR also defined in ../typedef.h
	}

	const Word Vocab::InitSpecialWord( const string& word_str)
	{
		FactorList factors;
		factors.push_back( 0); // store the special word string as the first factor
		Word word;
		// define special word as Input word with one factor and isNonTerminal=false
		word.CreateFromString( Input, factors, word_str, false ); // Input is enum defined in ../typedef.h
		// TODO not sure if this will work properly:
		// 	- word comparison can fail because the last parameter (isNonTerminal)
		// 		in function CreateFromString may not match properly created words
		// 	- special word is Input word but what about Output words?
		// 		- currently Input/Output variable is not stored in class Word, but in the future???
		return word;
	}
	
	// get wordID_t index for word represented as string
	wordID_t Vocab::GetWordID(const std::string& word_str, 
		const FactorDirection& direction, const FactorList& factors, bool isNonTerminal)
	{
		// get id for factored string
		Word word;
		word.CreateFromString( direction, factors, word_str, isNonTerminal);		
		return GetWordID( word);	
	}	

	wordID_t Vocab::GetWordID(const Word& word) 
	{
		// get id and possibly add to vocab 
		if (m_words2ids.find(word) == m_words2ids.end())
			if (!m_closed) {
				wordID_t id = m_words2ids.size() + 1;
				m_ids2words[id] = word;
				// update lookup tables
				m_words2ids[word] = id;
			} 
			else {
				return m_kOOVWordID;
			}
		wordID_t id = m_words2ids[word];
		return id;
	}
		
	Word& Vocab::GetWord(wordID_t id) 
	{
		// get word string given id
		return (m_ids2words.find(id) == m_ids2words.end()) ? m_kOOVWord : m_ids2words[id];
	}
	
	bool Vocab::InVocab(wordID_t id) 
	{
		return m_ids2words.find(id) != m_ids2words.end();
	}

	bool Vocab::InVocab(const Word& word) 
	{
		return m_words2ids.find(word) != m_words2ids.end();
	}
	
	bool Vocab::Save(const std::string & vocab_path) 
	{
		// save vocab as id -> word 
		FileHandler vcbout(vocab_path, std::ios::out);
		return Save(&vcbout);
	}
	
	bool Vocab::Save(FileHandler* vcbout) 
	{
		// then each vcb entry
		*vcbout << m_ids2words.size() << "\n";
		iterate(m_ids2words, iter)
			*vcbout << iter->second << "\t" << iter->first << "\n";
		return true;
	}
	
	bool Vocab::Load(const std::string & vocab_path, const FactorDirection& direction, 
		const FactorList& factors, bool closed) 
	{
		FileHandler vcbin(vocab_path, std::ios::in);
		std::cerr << "Loading vocab from " << vocab_path << std::endl;
		return Load(&vcbin, direction, factors, closed);
	}
	
	bool Vocab::Load(FileHandler* vcbin, const FactorDirection& direction, 
		const FactorList& factors, bool closed) {
		// load vocab id -> word mapping 
		m_words2ids.clear();	// reset mapping
		m_ids2words.clear();
		std::string line, word_str;
		wordID_t id;
		assert(getline(*vcbin, line));
		std::istringstream first(line.c_str());
		uint32_t vcbsize(0);
		first >> vcbsize;
		uint32_t loadedsize = 0;
		while (loadedsize++ < vcbsize && getline(*vcbin, line)) {
			std::istringstream entry(line.c_str());
			entry >> word_str;
			Word word;
			word.CreateFromString( direction, factors, word_str, false); // TODO set correctly isNonTerminal
			entry >> id; 
			// may be no id (i.e. file may just be a word list)
			if (id == 0 && word != GetkOOVWord())  
				id = m_ids2words.size() + 1;	// assign ids sequentially starting from 1
			assert(m_ids2words.count(id) == 0 && m_words2ids.count(word) == 0);
			m_ids2words[id] = word;
			m_words2ids[word] = id;
		}
		m_closed = closed;	// once loaded fix vocab ?
		std::cerr << "Loaded vocab with " << m_ids2words.size() << " words." << std::endl;
		return true;
	}
	void Vocab::PrintVocab() 
	{
		iterate(m_ids2words, iter)
			std::cerr << iter->second << "\t" << iter->first << "\n";
		iterate(m_words2ids, iter)
			std::cerr << iter->second << "\t" << iter->first << "\n";
	}

} //end namespace