コード例 #1
0
ファイル: CollectKnownItemsFn.java プロジェクト: Benoye/oryx
 private static String setToString(LongFloatMap map) {
   LongPrimitiveIterator it = map.keySetIterator();
   Collection<String> keyStrings = Lists.newArrayListWithCapacity(map.size());
   while (it.hasNext()) {
     keyStrings.add(Long.toString(it.nextLong()));
   }
   return DelimitedDataUtils.encode(',', keyStrings);
 }
コード例 #2
0
  @Override
  public void process(
      Pair<Pair<Long, Integer>, Iterable<NumericIDValue>> input,
      Emitter<Pair<Long, NumericIDValue>> emitter) {
    Pair<Long, Integer> key = input.first();
    long currentUserID = key.first();

    if (key.second() == BEFORE) {

      // Last old data had no match, just output it
      if (previousUserPrefs != null) {
        Preconditions.checkNotNull(previousUserID);
        output(previousUserID, previousUserPrefs, null, null, emitter);
        previousUserPrefs = null;
        previousUserID = null;
      }

      LongFloatMap oldPrefs = new LongFloatMap();
      for (NumericIDValue itemPref : input.second()) {
        float oldPrefValue = itemPref.getValue();
        Preconditions.checkState(!Float.isNaN(oldPrefValue), "No prior pref value?");
        // Apply decay factor here, if applicable:
        oldPrefs.increment(itemPref.getID(), doDecay ? oldPrefValue * decayFactor : oldPrefValue);
      }

      previousUserPrefs = oldPrefs;
      previousUserID = currentUserID;

    } else {
      // Last old data had no match, just output it
      if (previousUserPrefs != null && currentUserID != previousUserID) {
        Preconditions.checkNotNull(previousUserID);
        output(previousUserID, previousUserPrefs, null, null, emitter);
        previousUserPrefs = null;
        previousUserID = null;
      }

      LongFloatMap newPrefs = new LongFloatMap();
      LongSet removedItemIDs = new LongSet();
      for (NumericIDValue itemPref : input.second()) {
        long itemID = itemPref.getID();
        float newPrefValue = itemPref.getValue();
        if (Float.isNaN(newPrefValue)) {
          removedItemIDs.add(itemID);
        } else {
          newPrefs.increment(itemID, newPrefValue);
        }
      }

      output(currentUserID, previousUserPrefs, newPrefs, removedItemIDs, emitter);

      previousUserPrefs = null;
      previousUserID = null;
    }
  }
コード例 #3
0
  private void output(
      long userID,
      LongFloatMap oldPrefs,
      LongFloatMap newPrefs,
      LongSet removedItemIDs,
      Emitter<Pair<Long, NumericIDValue>> emitter) {
    // Old prefs may be null when there is no previous generation, for example, or the user is new.
    // First, write out existing prefs, possibly updated by new values
    if (oldPrefs != null && !oldPrefs.isEmpty()) {
      for (LongFloatMap.MapEntry entry : oldPrefs.entrySet()) {
        long itemID = entry.getKey();
        float oldPrefValue = entry.getValue();
        Preconditions.checkState(!Float.isNaN(oldPrefValue), "No prior pref value?");

        // May be NaN if no new data at all, or new data has no update:
        float sum = oldPrefValue;
        if (newPrefs != null) {
          float newPrefValue = newPrefs.get(itemID);
          if (!Float.isNaN(newPrefValue)) {
            sum += newPrefValue;
          }
        }

        boolean remove = false;
        if (removedItemIDs != null && removedItemIDs.contains(itemID)) {
          remove = true;
        } else if (FastMath.abs(sum) <= zeroThreshold) {
          remove = true;
        }

        if (!remove) {
          emitter.emit(Pair.of(userID, new NumericIDValue(itemID, sum)));
        }
      }
    }

    // Now output new data, that didn't exist in old prefs
    if (newPrefs != null && !newPrefs.isEmpty()) {
      for (LongFloatMap.MapEntry entry : newPrefs.entrySet()) {
        long itemID = entry.getKey();
        if (oldPrefs == null || !oldPrefs.containsKey(itemID)) {
          // It wasn't already written. If it exists in newPrefs, it's also not removed
          float newPrefValue = entry.getValue();
          if (FastMath.abs(newPrefValue) > zeroThreshold) {
            emitter.emit(Pair.of(userID, new NumericIDValue(itemID, newPrefValue)));
          }
        }
      }
    }
  }