diff options
author | 2013-06-24 01:11:32 +0900 | |
---|---|---|
committer | 2013-06-24 17:04:40 +0900 | |
commit | e28eba5074664d5716b8e58b8d0a235746b261eb (patch) | |
tree | 7f055d1617a9d621fb5b51eb4d52a9a93d9bad44 /java/src/com/android/inputmethod/latin/UserHistoryForgettingCurveUtils.java | |
parent | 80a4b7c92e96d359e0360f85b2ed3ed128ad0f3f (diff) | |
download | latinime-e28eba5074664d5716b8e58b8d0a235746b261eb.tar.gz latinime-e28eba5074664d5716b8e58b8d0a235746b261eb.tar.xz latinime-e28eba5074664d5716b8e58b8d0a235746b261eb.zip |
Move util classes to the latin/utils directory
Change-Id: I1c5b27c8edf231680edb8d96f63b9d04cfc6a6fa
Diffstat (limited to 'java/src/com/android/inputmethod/latin/UserHistoryForgettingCurveUtils.java')
-rw-r--r-- | java/src/com/android/inputmethod/latin/UserHistoryForgettingCurveUtils.java | 222 |
1 files changed, 0 insertions, 222 deletions
diff --git a/java/src/com/android/inputmethod/latin/UserHistoryForgettingCurveUtils.java b/java/src/com/android/inputmethod/latin/UserHistoryForgettingCurveUtils.java deleted file mode 100644 index 9053d709b..000000000 --- a/java/src/com/android/inputmethod/latin/UserHistoryForgettingCurveUtils.java +++ /dev/null @@ -1,222 +0,0 @@ -/* - * Copyright (C) 2012 The Android Open Source Project - * - * Licensed under the Apache License, Version 2.0 (the "License"); - * you may not use this file except in compliance with the License. - * You may obtain a copy of the License at - * - * http://www.apache.org/licenses/LICENSE-2.0 - * - * Unless required by applicable law or agreed to in writing, software - * distributed under the License is distributed on an "AS IS" BASIS, - * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. - * See the License for the specific language governing permissions and - * limitations under the License. - */ - -package com.android.inputmethod.latin; - -import android.text.format.DateUtils; -import android.util.Log; - -public final class UserHistoryForgettingCurveUtils { - private static final String TAG = UserHistoryForgettingCurveUtils.class.getSimpleName(); - private static final boolean DEBUG = false; - private static final int FC_FREQ_MAX = 127; - /* package */ static final int COUNT_MAX = 3; - private static final int FC_LEVEL_MAX = 3; - /* package */ static final int ELAPSED_TIME_MAX = 15; - private static final int ELAPSED_TIME_INTERVAL_HOURS = 6; - private static final long ELAPSED_TIME_INTERVAL_MILLIS = ELAPSED_TIME_INTERVAL_HOURS - * DateUtils.HOUR_IN_MILLIS; - private static final int HALF_LIFE_HOURS = 48; - private static final int MAX_PUSH_ELAPSED = (FC_LEVEL_MAX + 1) * (ELAPSED_TIME_MAX + 1); - - private UserHistoryForgettingCurveUtils() { - // This utility class is not publicly instantiable. - } - - public static final class ForgettingCurveParams { - private byte mFc; - long mLastTouchedTime = 0; - private final boolean mIsValid; - - private void updateLastTouchedTime() { - mLastTouchedTime = System.currentTimeMillis(); - } - - public ForgettingCurveParams(boolean isValid) { - this(System.currentTimeMillis(), isValid); - } - - private ForgettingCurveParams(long now, boolean isValid) { - this(pushCount((byte)0, isValid), now, now, isValid); - } - - /** This constructor is called when the user history bigram dictionary is being restored. */ - public ForgettingCurveParams(int fc, long now, long last) { - // All words with level >= 1 had been saved. - // Invalid words with level == 0 had been saved. - // Valid words words with level == 0 had *not* been saved. - this(fc, now, last, fcToLevel((byte)fc) > 0); - } - - private ForgettingCurveParams(int fc, long now, long last, boolean isValid) { - mIsValid = isValid; - mFc = (byte)fc; - mLastTouchedTime = last; - updateElapsedTime(now); - } - - public boolean isValid() { - return mIsValid; - } - - public byte getFc() { - updateElapsedTime(System.currentTimeMillis()); - return mFc; - } - - public int getFrequency() { - updateElapsedTime(System.currentTimeMillis()); - return UserHistoryForgettingCurveUtils.fcToFreq(mFc); - } - - public int notifyTypedAgainAndGetFrequency() { - updateLastTouchedTime(); - // TODO: Check whether this word is valid or not - mFc = pushCount(mFc, false); - return UserHistoryForgettingCurveUtils.fcToFreq(mFc); - } - - private void updateElapsedTime(long now) { - final int elapsedTimeCount = - (int)((now - mLastTouchedTime) / ELAPSED_TIME_INTERVAL_MILLIS); - if (elapsedTimeCount <= 0) { - return; - } - if (elapsedTimeCount >= MAX_PUSH_ELAPSED) { - mLastTouchedTime = now; - mFc = 0; - return; - } - for (int i = 0; i < elapsedTimeCount; ++i) { - mLastTouchedTime += ELAPSED_TIME_INTERVAL_MILLIS; - mFc = pushElapsedTime(mFc); - } - } - } - - /* package */ static int fcToElapsedTime(byte fc) { - return fc & 0x0F; - } - - /* package */ static int fcToCount(byte fc) { - return (fc >> 4) & 0x03; - } - - /* package */ static int fcToLevel(byte fc) { - return (fc >> 6) & 0x03; - } - - private static int calcFreq(int elapsedTime, int count, int level) { - if (level <= 0) { - // Reserved words, just return -1 - return -1; - } - if (count == COUNT_MAX) { - // Temporary promote because it's frequently typed recently - ++level; - } - final int et = Math.min(FC_FREQ_MAX, Math.max(0, elapsedTime)); - final int l = Math.min(FC_LEVEL_MAX, Math.max(0, level)); - return MathUtils.SCORE_TABLE[l - 1][et]; - } - - /* pakcage */ static byte calcFc(int elapsedTime, int count, int level) { - final int et = Math.min(FC_FREQ_MAX, Math.max(0, elapsedTime)); - final int c = Math.min(COUNT_MAX, Math.max(0, count)); - final int l = Math.min(FC_LEVEL_MAX, Math.max(0, level)); - return (byte)(et | (c << 4) | (l << 6)); - } - - public static int fcToFreq(byte fc) { - final int elapsedTime = fcToElapsedTime(fc); - final int count = fcToCount(fc); - final int level = fcToLevel(fc); - return calcFreq(elapsedTime, count, level); - } - - public static byte pushElapsedTime(byte fc) { - int elapsedTime = fcToElapsedTime(fc); - int count = fcToCount(fc); - int level = fcToLevel(fc); - if (elapsedTime >= ELAPSED_TIME_MAX) { - // Downgrade level - elapsedTime = 0; - count = COUNT_MAX; - --level; - } else { - ++elapsedTime; - } - return calcFc(elapsedTime, count, level); - } - - public static byte pushCount(byte fc, boolean isValid) { - final int elapsedTime = fcToElapsedTime(fc); - int count = fcToCount(fc); - int level = fcToLevel(fc); - if ((elapsedTime == 0 && count >= COUNT_MAX) || (isValid && level == 0)) { - // Upgrade level - ++level; - count = 0; - if (DEBUG) { - Log.d(TAG, "Upgrade level."); - } - } else { - ++count; - } - return calcFc(0, count, level); - } - - // TODO: isValid should be false for a word whose frequency is 0, - // or that is not in the dictionary. - /** - * Check wheather we should save the bigram to the SQL DB or not - */ - public static boolean needsToSave(byte fc, boolean isValid, boolean addLevel0Bigram) { - int level = fcToLevel(fc); - if (level == 0) { - if (isValid || !addLevel0Bigram) { - return false; - } - } - final int elapsedTime = fcToElapsedTime(fc); - return (elapsedTime < ELAPSED_TIME_MAX - 1 || level > 0); - } - - private static final class MathUtils { - public static final int[][] SCORE_TABLE = new int[FC_LEVEL_MAX][ELAPSED_TIME_MAX + 1]; - static { - for (int i = 0; i < FC_LEVEL_MAX; ++i) { - final float initialFreq; - if (i >= 2) { - initialFreq = FC_FREQ_MAX; - } else if (i == 1) { - initialFreq = FC_FREQ_MAX / 2; - } else if (i == 0) { - initialFreq = FC_FREQ_MAX / 4; - } else { - continue; - } - for (int j = 0; j < ELAPSED_TIME_MAX; ++j) { - final float elapsedHours = j * ELAPSED_TIME_INTERVAL_HOURS; - final float freq = initialFreq - * (float)Math.pow(initialFreq, elapsedHours / HALF_LIFE_HOURS); - final int intFreq = Math.min(FC_FREQ_MAX, Math.max(0, (int)freq)); - SCORE_TABLE[i][j] = intFreq; - } - } - } - } -} |