Prepare supporting n-gram for user history dictionary.

Bug:17097992
Change-Id: Ic8bfde3d4cc0e720bf7681e08e16fb2ad94d5670
This commit is contained in:
Keisuke Kuroyanagi 2014-09-22 18:18:50 +09:00
parent b51412a05c
commit ddfaeff544
3 changed files with 33 additions and 12 deletions

View file

@ -126,6 +126,13 @@ public class PrevWordsInfo {
}
}
public PrevWordsInfo getTrimmedPrevWordsInfo(final int maxPrevWordCount) {
final int newSize = Math.min(maxPrevWordCount, mPrevWordsInfo.length);
// TODO: Quit creating a new array.
final WordInfo[] prevWordsInfo = Arrays.copyOf(mPrevWordsInfo, newSize);
return new PrevWordsInfo(prevWordsInfo);
}
public int getPrevWordCount() {
return mPrevWordsInfo.length;
}

View file

@ -35,6 +35,7 @@ import java.util.Locale;
*/
public class UserHistoryDictionary extends DecayingExpandableBinaryDictionaryBase {
/* package */ static final String NAME = UserHistoryDictionary.class.getSimpleName();
private final static int SUPPORTED_NGRAM = 2; // TODO: 3
// TODO: Make this constructor private
/* package */ UserHistoryDictionary(final Context context, final Locale locale) {
@ -61,9 +62,7 @@ public class UserHistoryDictionary extends DecayingExpandableBinaryDictionaryBas
public static void addToDictionary(final ExpandableBinaryDictionary userHistoryDictionary,
final PrevWordsInfo prevWordsInfo, final String word, final boolean isValid,
final int timestamp, final DistracterFilter distracterFilter) {
final CharSequence prevWord = prevWordsInfo.mPrevWordsInfo[0].mWord;
if (word.length() > Constants.DICTIONARY_MAX_WORD_LENGTH ||
(prevWord != null && prevWord.length() > Constants.DICTIONARY_MAX_WORD_LENGTH)) {
if (word.length() > Constants.DICTIONARY_MAX_WORD_LENGTH) {
return;
}
final int frequency = isValid ?
@ -71,17 +70,29 @@ public class UserHistoryDictionary extends DecayingExpandableBinaryDictionaryBas
userHistoryDictionary.addUnigramEntryWithCheckingDistracter(word, frequency,
null /* shortcutTarget */, 0 /* shortcutFreq */, false /* isNotAWord */,
false /* isBlacklisted */, timestamp, distracterFilter);
// Do not insert a word as a bigram of itself
if (TextUtils.equals(word, prevWord)) {
return;
}
if (null != prevWord) {
if (prevWordsInfo.mPrevWordsInfo[0].mIsBeginningOfSentence) {
// Beginning-of-Sentence n-gram entry is treated as a n-gram entry of invalid word.
userHistoryDictionary.addNgramEntry(prevWordsInfo, word,
final boolean isBeginningOfSentenceContext =
prevWordsInfo.mPrevWordsInfo[0].mIsBeginningOfSentence;
final PrevWordsInfo prevWordsInfoToBeSaved =
prevWordsInfo.getTrimmedPrevWordsInfo(SUPPORTED_NGRAM - 1);
for (int i = 0; i < prevWordsInfoToBeSaved.getPrevWordCount(); i++) {
final CharSequence prevWord = prevWordsInfoToBeSaved.mPrevWordsInfo[i].mWord;
if (prevWord == null || (prevWord.length() > Constants.DICTIONARY_MAX_WORD_LENGTH)) {
return;
}
// Do not insert a word as a bigram of itself
if (i == 0 && TextUtils.equals(word, prevWord)) {
return;
}
if (isBeginningOfSentenceContext) {
// Beginning-of-Sentence n-gram entry is added as an n-gram entry of an OOV word.
userHistoryDictionary.addNgramEntry(
prevWordsInfoToBeSaved.getTrimmedPrevWordsInfo(i + 1), word,
FREQUENCY_FOR_WORDS_NOT_IN_DICTS, timestamp);
} else {
userHistoryDictionary.addNgramEntry(prevWordsInfo, word, frequency, timestamp);
userHistoryDictionary.addNgramEntry(
prevWordsInfoToBeSaved.getTrimmedPrevWordsInfo(i + 1), word, frequency,
timestamp);
}
}
}

View file

@ -166,6 +166,9 @@ void Ver4PatriciaTriePolicy::iterateNgramEntries(const WordIdArrayView prevWordI
for (const auto entry : languageModelDictContent->getProbabilityEntries(
prevWordIds.limit(i))) {
const ProbabilityEntry &probabilityEntry = entry.getProbabilityEntry();
if (!probabilityEntry.isValid()) {
continue;
}
const int probability = probabilityEntry.hasHistoricalInfo() ?
ForgettingCurveUtils::decodeProbability(
probabilityEntry.getHistoricalInfo(), mHeaderPolicy)