mosesdecoder/lm/builder/print.cc
2013-01-18 15:59:51 +00:00

136 lines
4.0 KiB
C++

#include "lm/builder/print.hh"
#include "util/double-conversion/double-conversion.h"
#include "util/double-conversion/utils.h"
#include "util/file.hh"
#include "util/mmap.hh"
#include "util/scoped.hh"
#include "util/stream/timer.hh"
#define BOOST_LEXICAL_CAST_ASSUME_C_LOCALE
#include <boost/lexical_cast.hpp>
#include <sstream>
#include <string.h>
namespace lm { namespace builder {
VocabReconstitute::VocabReconstitute(int fd) {
uint64_t size = util::SizeOrThrow(fd);
util::MapRead(util::POPULATE_OR_READ, fd, 0, size, memory_);
const char *const start = static_cast<const char*>(memory_.get());
const char *i;
for (i = start; i != start + size; i += strlen(i) + 1) {
map_.push_back(i);
}
// Last one for LookupPiece.
map_.push_back(i);
}
namespace {
class OutputManager {
public:
static const std::size_t kOutBuf = 1048576;
// Does not take ownership of out.
explicit OutputManager(int out)
: buf_(util::MallocOrThrow(kOutBuf)),
builder_(static_cast<char*>(buf_.get()), kOutBuf),
// Mostly the default but with inf instead. And no flags.
convert_(double_conversion::DoubleToStringConverter::NO_FLAGS, "inf", "NaN", 'e', -6, 21, 6, 0),
fd_(out) {}
~OutputManager() {
Flush();
}
OutputManager &operator<<(float value) {
// Odd, but this is the largest number found in the comments.
EnsureRemaining(double_conversion::DoubleToStringConverter::kMaxPrecisionDigits + 8);
convert_.ToShortestSingle(value, &builder_);
return *this;
}
OutputManager &operator<<(StringPiece str) {
if (str.size() > kOutBuf) {
Flush();
util::WriteOrThrow(fd_, str.data(), str.size());
} else {
EnsureRemaining(str.size());
builder_.AddSubstring(str.data(), str.size());
}
return *this;
}
// Inefficient!
OutputManager &operator<<(unsigned val) {
return *this << boost::lexical_cast<std::string>(val);
}
OutputManager &operator<<(char c) {
EnsureRemaining(1);
builder_.AddCharacter(c);
return *this;
}
void Flush() {
util::WriteOrThrow(fd_, buf_.get(), builder_.position());
builder_.Reset();
}
private:
void EnsureRemaining(std::size_t amount) {
if (static_cast<std::size_t>(builder_.size() - builder_.position()) < amount) {
Flush();
}
}
util::scoped_malloc buf_;
double_conversion::StringBuilder builder_;
double_conversion::DoubleToStringConverter convert_;
int fd_;
};
} // namespace
PrintARPA::PrintARPA(const VocabReconstitute &vocab, const std::vector<uint64_t> &counts, const HeaderInfo* header_info, int out_fd)
: vocab_(vocab), out_fd_(out_fd) {
std::stringstream stream;
if (header_info) {
stream << "# Input file: " << header_info->input_file << '\n';
stream << "# Token count: " << header_info->token_count << '\n';
stream << "# Smoothing: Modified Kneser-Ney" << '\n';
}
stream << "\\data\\\n";
for (size_t i = 0; i < counts.size(); ++i) {
stream << "ngram " << (i+1) << '=' << counts[i] << '\n';
}
stream << '\n';
std::string as_string(stream.str());
util::WriteOrThrow(out_fd, as_string.data(), as_string.size());
}
void PrintARPA::Run(const ChainPositions &positions) {
UTIL_TIMER("(%w s) Wrote ARPA file\n");
OutputManager out(out_fd_);
for (unsigned order = 1; order <= positions.size(); ++order) {
out << "\\" << order << "-grams:" << '\n';
for (NGramStream stream(positions[order - 1]); stream; ++stream) {
// Correcting for numerical precision issues. Take that IRST.
out << std::min(0.0f, stream->Value().complete.prob) << '\t' << vocab_.Lookup(*stream->begin());
for (const WordIndex *i = stream->begin() + 1; i != stream->end(); ++i) {
out << ' ' << vocab_.Lookup(*i);
}
float backoff = stream->Value().complete.backoff;
if (backoff != 0.0)
out << '\t' << backoff;
out << '\n';
}
out << '\n';
}
out << "\\end\\\n";
}
}} // namespaces