mirror of
https://github.com/fanlumaster/googlepinyinime-rev.git
synced 2025-07-18 17:08:00 +08:00
add all necessary configs
This commit is contained in:
fanlumaster
293
src/share/ngram.cpp
Normal file
293
src/share/ngram.cpp
Normal file
@ -0,0 +1,293 @@
|
||||
/*
|
||||
* Copyright (C) 2009 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.
|
||||
*/
|
||||
|
||||
#include <assert.h>
|
||||
#include <math.h>
|
||||
#include <stdio.h>
|
||||
#include <string.h>
|
||||
#include <time.h>
|
||||
#include "../include/mystdlib.h"
|
||||
#include "../include/ngram.h"
|
||||
|
||||
namespace ime_pinyin {
|
||||
|
||||
#define ADD_COUNT 0.3
|
||||
|
||||
int comp_double(const void *p1, const void *p2) {
|
||||
if (*static_cast<const double *>(p1) < *static_cast<const double *>(p2)) return -1;
|
||||
if (*static_cast<const double *>(p1) > *static_cast<const double *>(p2)) return 1;
|
||||
return 0;
|
||||
}
|
||||
|
||||
inline double distance(double freq, double code) {
|
||||
// return fabs(freq - code);
|
||||
return freq * fabs(log(freq) - log(code));
|
||||
}
|
||||
|
||||
// Find the index of the code value which is nearest to the given freq
|
||||
int qsearch_nearest(double code_book[], double freq, int start, int end) {
|
||||
if (start == end) return start;
|
||||
|
||||
if (start + 1 == end) {
|
||||
if (distance(freq, code_book[end]) > distance(freq, code_book[start])) return start;
|
||||
return end;
|
||||
}
|
||||
|
||||
int mid = (start + end) / 2;
|
||||
|
||||
if (code_book[mid] > freq)
|
||||
return qsearch_nearest(code_book, freq, start, mid);
|
||||
else
|
||||
return qsearch_nearest(code_book, freq, mid, end);
|
||||
}
|
||||
|
||||
size_t update_code_idx(double freqs[], size_t num, double code_book[], CODEBOOK_TYPE *code_idx) {
|
||||
size_t changed = 0;
|
||||
for (size_t pos = 0; pos < num; pos++) {
|
||||
CODEBOOK_TYPE idx;
|
||||
idx = qsearch_nearest(code_book, freqs[pos], 0, kCodeBookSize - 1);
|
||||
if (idx != code_idx[pos]) changed++;
|
||||
code_idx[pos] = idx;
|
||||
}
|
||||
return changed;
|
||||
}
|
||||
|
||||
double recalculate_kernel(double freqs[], size_t num, double code_book[], CODEBOOK_TYPE *code_idx) {
|
||||
double ret = 0;
|
||||
|
||||
size_t *item_num = new size_t[kCodeBookSize];
|
||||
assert(item_num);
|
||||
memset(item_num, 0, sizeof(size_t) * kCodeBookSize);
|
||||
|
||||
double *cb_new = new double[kCodeBookSize];
|
||||
assert(cb_new);
|
||||
memset(cb_new, 0, sizeof(double) * kCodeBookSize);
|
||||
|
||||
for (size_t pos = 0; pos < num; pos++) {
|
||||
ret += distance(freqs[pos], code_book[code_idx[pos]]);
|
||||
|
||||
cb_new[code_idx[pos]] += freqs[pos];
|
||||
item_num[code_idx[pos]] += 1;
|
||||
}
|
||||
|
||||
for (size_t code = 0; code < kCodeBookSize; code++) {
|
||||
assert(item_num[code] > 0);
|
||||
code_book[code] = cb_new[code] / item_num[code];
|
||||
}
|
||||
|
||||
delete[] item_num;
|
||||
delete[] cb_new;
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
void iterate_codes(double freqs[], size_t num, double code_book[], CODEBOOK_TYPE *code_idx) {
|
||||
size_t iter_num = 0;
|
||||
double delta_last = 0;
|
||||
do {
|
||||
size_t changed = update_code_idx(freqs, num, code_book, code_idx);
|
||||
|
||||
double delta = recalculate_kernel(freqs, num, code_book, code_idx);
|
||||
|
||||
if (kPrintDebug0) {
|
||||
printf("---Unigram codebook iteration: %d : %d, %.9f\n", iter_num, changed, delta);
|
||||
}
|
||||
iter_num++;
|
||||
|
||||
if (iter_num > 1 && (delta == 0 || fabs(delta_last - delta) / fabs(delta) < 0.000000001)) break;
|
||||
delta_last = delta;
|
||||
} while (true);
|
||||
}
|
||||
|
||||
NGram *NGram::instance_ = NULL;
|
||||
|
||||
NGram::NGram() {
|
||||
initialized_ = false;
|
||||
idx_num_ = 0;
|
||||
lma_freq_idx_ = NULL;
|
||||
sys_score_compensation_ = 0;
|
||||
|
||||
#ifdef ___BUILD_MODEL___
|
||||
freq_codes_df_ = NULL;
|
||||
#endif
|
||||
freq_codes_ = NULL;
|
||||
}
|
||||
|
||||
NGram::~NGram() {
|
||||
if (NULL != lma_freq_idx_) free(lma_freq_idx_);
|
||||
|
||||
#ifdef ___BUILD_MODEL___
|
||||
if (NULL != freq_codes_df_) free(freq_codes_df_);
|
||||
#endif
|
||||
|
||||
if (NULL != freq_codes_) free(freq_codes_);
|
||||
}
|
||||
|
||||
NGram &NGram::get_instance() {
|
||||
if (NULL == instance_) instance_ = new NGram();
|
||||
return *instance_;
|
||||
}
|
||||
|
||||
bool NGram::save_ngram(FILE *fp) {
|
||||
if (!initialized_ || NULL == fp) return false;
|
||||
|
||||
if (0 == idx_num_ || NULL == freq_codes_ || NULL == lma_freq_idx_) return false;
|
||||
|
||||
if (fwrite(&idx_num_, sizeof(uint32), 1, fp) != 1) return false;
|
||||
|
||||
if (fwrite(freq_codes_, sizeof(LmaScoreType), kCodeBookSize, fp) != kCodeBookSize) return false;
|
||||
|
||||
if (fwrite(lma_freq_idx_, sizeof(CODEBOOK_TYPE), idx_num_, fp) != idx_num_) return false;
|
||||
|
||||
return true;
|
||||
}
|
||||
|
||||
bool NGram::load_ngram(FILE *fp) {
|
||||
if (NULL == fp) return false;
|
||||
|
||||
initialized_ = false;
|
||||
|
||||
if (fread(&idx_num_, sizeof(uint32), 1, fp) != 1) return false;
|
||||
|
||||
if (NULL != lma_freq_idx_) free(lma_freq_idx_);
|
||||
|
||||
if (NULL != freq_codes_) free(freq_codes_);
|
||||
|
||||
lma_freq_idx_ = static_cast<CODEBOOK_TYPE *>(malloc(idx_num_ * sizeof(CODEBOOK_TYPE)));
|
||||
freq_codes_ = static_cast<LmaScoreType *>(malloc(kCodeBookSize * sizeof(LmaScoreType)));
|
||||
|
||||
if (NULL == lma_freq_idx_ || NULL == freq_codes_) return false;
|
||||
|
||||
if (fread(freq_codes_, sizeof(LmaScoreType), kCodeBookSize, fp) != kCodeBookSize) return false;
|
||||
|
||||
if (fread(lma_freq_idx_, sizeof(CODEBOOK_TYPE), idx_num_, fp) != idx_num_) return false;
|
||||
|
||||
initialized_ = true;
|
||||
|
||||
total_freq_none_sys_ = 0;
|
||||
return true;
|
||||
}
|
||||
|
||||
void NGram::set_total_freq_none_sys(size_t freq_none_sys) {
|
||||
total_freq_none_sys_ = freq_none_sys;
|
||||
if (0 == total_freq_none_sys_) {
|
||||
sys_score_compensation_ = 0;
|
||||
} else {
|
||||
double factor = static_cast<double>(kSysDictTotalFreq) / (kSysDictTotalFreq + total_freq_none_sys_);
|
||||
sys_score_compensation_ = static_cast<float>(log(factor) * kLogValueAmplifier);
|
||||
}
|
||||
}
|
||||
|
||||
// The caller makes sure this oject is initialized.
|
||||
float NGram::get_uni_psb(LemmaIdType lma_id) { return static_cast<float>(freq_codes_[lma_freq_idx_[lma_id]]) + sys_score_compensation_; }
|
||||
|
||||
float NGram::convert_psb_to_score(double psb) {
|
||||
float score = static_cast<float>(log(psb) * static_cast<double>(kLogValueAmplifier));
|
||||
if (score > static_cast<float>(kMaxScore)) {
|
||||
score = static_cast<float>(kMaxScore);
|
||||
}
|
||||
return score;
|
||||
}
|
||||
|
||||
#ifdef ___BUILD_MODEL___
|
||||
bool NGram::build_unigram(LemmaEntry *lemma_arr, size_t lemma_num, LemmaIdType next_idx_unused) {
|
||||
if (NULL == lemma_arr || 0 == lemma_num || next_idx_unused <= 1) return false;
|
||||
|
||||
double total_freq = 0;
|
||||
double *freqs = new double[next_idx_unused];
|
||||
if (NULL == freqs) return false;
|
||||
|
||||
freqs[0] = ADD_COUNT;
|
||||
total_freq += freqs[0];
|
||||
LemmaIdType idx_now = 0;
|
||||
for (size_t pos = 0; pos < lemma_num; pos++) {
|
||||
if (lemma_arr[pos].idx_by_hz == idx_now) continue;
|
||||
idx_now++;
|
||||
|
||||
assert(lemma_arr[pos].idx_by_hz == idx_now);
|
||||
|
||||
freqs[idx_now] = lemma_arr[pos].freq;
|
||||
if (freqs[idx_now] <= 0) freqs[idx_now] = 0.3;
|
||||
|
||||
total_freq += freqs[idx_now];
|
||||
}
|
||||
|
||||
double max_freq = 0;
|
||||
idx_num_ = idx_now + 1;
|
||||
assert(idx_now + 1 == next_idx_unused);
|
||||
|
||||
for (size_t pos = 0; pos < idx_num_; pos++) {
|
||||
freqs[pos] = freqs[pos] / total_freq;
|
||||
assert(freqs[pos] > 0);
|
||||
if (freqs[pos] > max_freq) max_freq = freqs[pos];
|
||||
}
|
||||
|
||||
// calculate the code book
|
||||
if (NULL == freq_codes_df_) freq_codes_df_ = new double[kCodeBookSize];
|
||||
assert(freq_codes_df_);
|
||||
memset(freq_codes_df_, 0, sizeof(double) * kCodeBookSize);
|
||||
|
||||
if (NULL == freq_codes_) freq_codes_ = new LmaScoreType[kCodeBookSize];
|
||||
assert(freq_codes_);
|
||||
memset(freq_codes_, 0, sizeof(LmaScoreType) * kCodeBookSize);
|
||||
|
||||
size_t freq_pos = 0;
|
||||
for (size_t code_pos = 0; code_pos < kCodeBookSize; code_pos++) {
|
||||
bool found = true;
|
||||
|
||||
while (found) {
|
||||
found = false;
|
||||
double cand = freqs[freq_pos];
|
||||
for (size_t i = 0; i < code_pos; i++)
|
||||
if (freq_codes_df_[i] == cand) {
|
||||
found = true;
|
||||
break;
|
||||
}
|
||||
if (found) freq_pos++;
|
||||
}
|
||||
|
||||
freq_codes_df_[code_pos] = freqs[freq_pos];
|
||||
freq_pos++;
|
||||
}
|
||||
|
||||
myqsort(freq_codes_df_, kCodeBookSize, sizeof(double), comp_double);
|
||||
|
||||
if (NULL == lma_freq_idx_) lma_freq_idx_ = new CODEBOOK_TYPE[idx_num_];
|
||||
assert(lma_freq_idx_);
|
||||
|
||||
iterate_codes(freqs, idx_num_, freq_codes_df_, lma_freq_idx_);
|
||||
|
||||
delete[] freqs;
|
||||
|
||||
if (kPrintDebug0) {
|
||||
printf("\n------Language Model Unigram Codebook------\n");
|
||||
}
|
||||
|
||||
for (size_t code_pos = 0; code_pos < kCodeBookSize; code_pos++) {
|
||||
double log_score = log(freq_codes_df_[code_pos]);
|
||||
float final_score = convert_psb_to_score(freq_codes_df_[code_pos]);
|
||||
if (kPrintDebug0) {
|
||||
printf("code:%d, probability:%.9f, log score:%.3f, final score: %.3f\n", code_pos, freq_codes_df_[code_pos], log_score, final_score);
|
||||
}
|
||||
freq_codes_[code_pos] = static_cast<LmaScoreType>(final_score);
|
||||
}
|
||||
|
||||
initialized_ = true;
|
||||
return true;
|
||||
}
|
||||
#endif
|
||||
|
||||
} // namespace ime_pinyin
|
||||
Reference in New Issue
Block a user