nyancrimew
/
LatinIME
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

Merge "Checking key edit distance of candidate words for gesture scoring."

main
Keisuke Kuroynagi 2013-05-07 11:48:54 +00:00 committed by Android (Google) Code Review
parent a9dd74cf3f a09f9709e0
commit b90a86b362
4 changed files with 197 additions and 42 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

47
native/jni/src/correction.cpp
View File

@ -23,6 +23,8 @@
#include "defines.h"
#include "proximity_info_state.h"
#include "suggest_utils.h"
#include "suggest/policyimpl/utils/edit_distance.h"
#include "suggest/policyimpl/utils/damerau_levenshtein_edit_distance_policy.h"
namespace latinime {
@ -906,50 +908,11 @@ inline static bool isUpperCase(unsigned short c) {
return totalFreq;
}
/* Damerau-Levenshtein distance */
inline static int editDistanceInternal(int *editDistanceTable, const int *before,
const int beforeLength, const int *after, const int afterLength) {
// dp[li][lo] dp[a][b] = dp[ a * lo + b]
int *dp = editDistanceTable;
const int li = beforeLength + 1;
const int lo = afterLength + 1;
for (int i = 0; i < li; ++i) {
dp[lo * i] = i;
}
for (int i = 0; i < lo; ++i) {
dp[i] = i;
}
for (int i = 0; i < li - 1; ++i) {
for (int j = 0; j < lo - 1; ++j) {
const int ci = toBaseLowerCase(before[i]);
const int co = toBaseLowerCase(after[j]);
const int cost = (ci == co) ? 0 : 1;
dp[(i + 1) * lo + (j + 1)] = min(dp[i * lo + (j + 1)] + 1,
min(dp[(i + 1) * lo + j] + 1, dp[i * lo + j] + cost));
if (i > 0 && j > 0 && ci == toBaseLowerCase(after[j - 1])
&& co == toBaseLowerCase(before[i - 1])) {
dp[(i + 1) * lo + (j + 1)] = min(
dp[(i + 1) * lo + (j + 1)], dp[(i - 1) * lo + (j - 1)] + cost);
}
}
}
if (DEBUG_EDIT_DISTANCE) {
AKLOGI("IN = %d, OUT = %d", beforeLength, afterLength);
for (int i = 0; i < li; ++i) {
for (int j = 0; j < lo; ++j) {
AKLOGI("EDIT[%d][%d], %d", i, j, dp[i * lo + j]);
}
}
}
return dp[li * lo - 1];
}
/* static */ int Correction::RankingAlgorithm::editDistance(const int *before,
const int beforeLength, const int *after, const int afterLength) {
int table[(beforeLength + 1) * (afterLength + 1)];
return editDistanceInternal(table, before, beforeLength, after, afterLength);
const DamerauLevenshteinEditDistancePolicy daemaruLevenshtein(
before, beforeLength, after, afterLength);
return static_cast<int>(EditDistance::getEditDistance(&daemaruLevenshtein));
}

79
native/jni/src/suggest/policyimpl/utils/damerau_levenshtein_edit_distance_policy.h Normal file
View File

@ -0,0 +1,79 @@
/*
* Copyright (C) 2013 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.
*/
#ifndef LATINIME_DAEMARU_LEVENSHTEIN_EDIT_DISTANCE_POLICY_H
#define LATINIME_DAEMARU_LEVENSHTEIN_EDIT_DISTANCE_POLICY_H
#include "char_utils.h"
#include "suggest/policyimpl/utils/edit_distance_policy.h"
namespace latinime {
class DamerauLevenshteinEditDistancePolicy : public EditDistancePolicy {
public:
DamerauLevenshteinEditDistancePolicy(const int *const string0, const int length0,
const int *const string1, const int length1)
: mString0(string0), mString0Length(length0), mString1(string1),
mString1Length(length1) {}
~DamerauLevenshteinEditDistancePolicy() {}
AK_FORCE_INLINE float getSubstitutionCost(const int index0, const int index1) const {
const int c0 = toBaseLowerCase(mString0[index0]);
const int c1 = toBaseLowerCase(mString1[index1]);
return (c0 == c1) ? 0.0f : 1.0f;
}
AK_FORCE_INLINE float getDeletionCost(const int index0, const int index1) const {
return 1.0f;
}
AK_FORCE_INLINE float getInsertionCost(const int index0, const int index1) const {
return 1.0f;
}
AK_FORCE_INLINE bool allowTransposition(const int index0, const int index1) const {
const int c0 = toBaseLowerCase(mString0[index0]);
const int c1 = toBaseLowerCase(mString1[index1]);
if (index0 > 0 && index1 > 0 && c0 == toBaseLowerCase(mString1[index1 - 1])
&& c1 == toBaseLowerCase(mString0[index0 - 1])) {
return true;
}
return false;
}
AK_FORCE_INLINE float getTranspositionCost(const int index0, const int index1) const {
return getSubstitutionCost(index0, index1);
}
AK_FORCE_INLINE int getString0Length() const {
return mString0Length;
}
AK_FORCE_INLINE int getString1Length() const {
return mString1Length;
}
private:
DISALLOW_COPY_AND_ASSIGN (DamerauLevenshteinEditDistancePolicy);
const int *const mString0;
const int mString0Length;
const int *const mString1;
const int mString1Length;
};
} // namespace latinime
#endif // LATINIME_DAEMARU_LEVENSHTEIN_EDIT_DISTANCE_POLICY_H

70
native/jni/src/suggest/policyimpl/utils/edit_distance.h Normal file
View File

@ -0,0 +1,70 @@
/*
* Copyright (C) 2013 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.
*/
#ifndef LATINIME_EDIT_DISTANCE_H
#define LATINIME_EDIT_DISTANCE_H
#include "defines.h"
#include "suggest/policyimpl/utils/edit_distance_policy.h"
namespace latinime {
class EditDistance {
public:
// CAVEAT: There may be performance penalty if you need the edit distance as an integer value.
AK_FORCE_INLINE static float getEditDistance(const EditDistancePolicy *const policy) {
const int beforeLength = policy->getString0Length();
const int afterLength = policy->getString1Length();
float dp[(beforeLength + 1) * (afterLength + 1)];
for (int i = 0; i <= beforeLength; ++i) {
dp[(afterLength + 1) * i] = i * policy->getInsertionCost(i - 1, -1);
}
for (int i = 0; i <= afterLength; ++i) {
dp[i] = i * policy->getDeletionCost(-1, i - 1);
}
for (int i = 0; i < beforeLength; ++i) {
for (int j = 0; j < afterLength; ++j) {
dp[(afterLength + 1) * (i + 1) + (j + 1)] = min(
dp[(afterLength + 1) * i + (j + 1)] + policy->getInsertionCost(i, j),
min(dp[(afterLength + 1) * (i + 1) + j] + policy->getDeletionCost(i, j),
dp[(afterLength + 1) * i + j]
+ policy->getSubstitutionCost(i, j)));
if (policy->allowTransposition(i, j)) {
dp[(afterLength + 1) * (i + 1) + (j + 1)] = min(
dp[(afterLength + 1) * (i + 1) + (j + 1)],
dp[(afterLength + 1) * (i - 1) + (j - 1)]
+ policy->getTranspositionCost(i, j));
}
}
}
if (DEBUG_EDIT_DISTANCE) {
AKLOGI("IN = %d, OUT = %d", beforeLength, afterLength);
for (int i = 0; i < beforeLength + 1; ++i) {
for (int j = 0; j < afterLength + 1; ++j) {
AKLOGI("EDIT[%d][%d], %f", i, j, dp[(afterLength + 1) * i + j]);
}
}
}
return dp[(beforeLength + 1) * (afterLength + 1) - 1];
}
private:
DISALLOW_IMPLICIT_CONSTRUCTORS(EditDistance);
};
} // namespace latinime
#endif // LATINIME_EDIT_DISTANCE_H

43
native/jni/src/suggest/policyimpl/utils/edit_distance_policy.h Normal file
View File

@ -0,0 +1,43 @@
/*
* Copyright (C) 2013 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.
*/
#ifndef LATINIME_EDIT_DISTANCE_POLICY_H
#define LATINIME_EDIT_DISTANCE_POLICY_H
#include "defines.h"
namespace latinime {
class EditDistancePolicy {
public:
virtual float getSubstitutionCost(const int index0, const int index1) const = 0;
virtual float getDeletionCost(const int index0, const int index1) const = 0;
virtual float getInsertionCost(const int index0, const int index1) const = 0;
virtual bool allowTransposition(const int index0, const int index1) const = 0;
virtual float getTranspositionCost(const int index0, const int index1) const = 0;
virtual int getString0Length() const = 0;
virtual int getString1Length() const = 0;
protected:
EditDistancePolicy() {}
virtual ~EditDistancePolicy() {}
private:
DISALLOW_COPY_AND_ASSIGN(EditDistancePolicy);
};
} // namespace latinime
#endif // LATINIME_EDIT_DISTANCE_POLICY_H