mosesdecoder/lm/ngram_query.hh
2015-09-29 16:58:02 +01:00

114 lines
3.4 KiB
C++

#ifndef LM_NGRAM_QUERY_H
#define LM_NGRAM_QUERY_H
#include "lm/enumerate_vocab.hh"
#include "lm/model.hh"
#include "util/file_stream.hh"
#include "util/file_piece.hh"
#include "util/usage.hh"
#include <cstdlib>
#include <string>
#include <cmath>
namespace lm {
namespace ngram {
class QueryPrinter {
public:
QueryPrinter(int fd, bool print_word, bool print_line, bool print_summary, bool flush)
: out_(fd), print_word_(print_word), print_line_(print_line), print_summary_(print_summary), flush_(flush) {}
void Word(StringPiece surface, WordIndex vocab, const FullScoreReturn &ret) {
if (!print_word_) return;
out_ << surface << '=' << vocab << ' ' << static_cast<unsigned int>(ret.ngram_length) << ' ' << ret.prob << '\t';
if (flush_) out_.flush();
}
void Line(uint64_t oov, float total) {
if (!print_line_) return;
out_ << "Total: " << total << " OOV: " << oov << '\n';
if (flush_) out_.flush();
}
void Summary(double ppl_including_oov, double ppl_excluding_oov, uint64_t corpus_oov, uint64_t corpus_tokens) {
if (!print_summary_) return;
out_ <<
"Perplexity including OOVs:\t" << ppl_including_oov << "\n"
"Perplexity excluding OOVs:\t" << ppl_excluding_oov << "\n"
"OOVs:\t" << corpus_oov << "\n"
"Tokens:\t" << corpus_tokens << '\n';
out_.flush();
}
private:
util::FileStream out_;
bool print_word_;
bool print_line_;
bool print_summary_;
bool flush_;
};
template <class Model, class Printer> void Query(const Model &model, bool sentence_context, Printer &printer) {
typename Model::State state, out;
lm::FullScoreReturn ret;
StringPiece word;
util::FilePiece in(0);
double corpus_total = 0.0;
double corpus_total_oov_only = 0.0;
uint64_t corpus_oov = 0;
uint64_t corpus_tokens = 0;
while (true) {
state = sentence_context ? model.BeginSentenceState() : model.NullContextState();
float total = 0.0;
uint64_t oov = 0;
while (in.ReadWordSameLine(word)) {
lm::WordIndex vocab = model.GetVocabulary().Index(word);
ret = model.FullScore(state, vocab, out);
if (vocab == model.GetVocabulary().NotFound()) {
++oov;
corpus_total_oov_only += ret.prob;
}
total += ret.prob;
printer.Word(word, vocab, ret);
++corpus_tokens;
state = out;
}
// If people don't have a newline after their last query, this won't add a </s>.
// Sue me.
try {
UTIL_THROW_IF('\n' != in.get(), util::Exception, "FilePiece is confused.");
} catch (const util::EndOfFileException &e) { break; }
if (sentence_context) {
ret = model.FullScore(state, model.GetVocabulary().EndSentence(), out);
total += ret.prob;
++corpus_tokens;
printer.Word("</s>", model.GetVocabulary().EndSentence(), ret);
}
printer.Line(oov, total);
corpus_total += total;
corpus_oov += oov;
}
printer.Summary(
pow(10.0, -(corpus_total / static_cast<double>(corpus_tokens))), // PPL including OOVs
pow(10.0, -((corpus_total - corpus_total_oov_only) / static_cast<double>(corpus_tokens - corpus_oov))), // PPL excluding OOVs
corpus_oov,
corpus_tokens);
}
template <class Model> void Query(const char *file, const Config &config, bool sentence_context, QueryPrinter &printer) {
Model model(file, config);
Query<Model, QueryPrinter>(model, sentence_context, printer);
}
} // namespace ngram
} // namespace lm
#endif // LM_NGRAM_QUERY_H