michael@0: /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #include "CharDistribution.h"
michael@0: 
michael@0: #include "JISFreq.tab"
michael@0: #include "Big5Freq.tab"
michael@0: #include "EUCKRFreq.tab"
michael@0: #include "EUCTWFreq.tab"
michael@0: #include "GB2312Freq.tab"
michael@0: #include "mozilla/ArrayUtils.h"
michael@0: 
michael@0: #define SURE_YES 0.99f
michael@0: #define SURE_NO  0.01f
michael@0: 
michael@0: //return confidence base on received data
michael@0: float CharDistributionAnalysis::GetConfidence(void)
michael@0: { 
michael@0:   //if we didn't receive any character in our consideration range, or the
michael@0:   // number of frequent characters is below the minimum threshold, return
michael@0:   // negative answer
michael@0:   if (mTotalChars <= 0 || mFreqChars <= mDataThreshold)
michael@0:     return SURE_NO;
michael@0: 
michael@0:   if (mTotalChars != mFreqChars) {
michael@0:     float r = mFreqChars / ((mTotalChars - mFreqChars) * mTypicalDistributionRatio);
michael@0: 
michael@0:     if (r < SURE_YES)
michael@0:       return r;
michael@0:   }
michael@0:   //normalize confidence, (we don't want to be 100% sure)
michael@0:   return SURE_YES;
michael@0: }
michael@0: 
michael@0: EUCTWDistributionAnalysis::EUCTWDistributionAnalysis()
michael@0: {
michael@0:   mCharToFreqOrder = EUCTWCharToFreqOrder;
michael@0:   mTableSize = mozilla::ArrayLength(EUCTWCharToFreqOrder);
michael@0:   mTypicalDistributionRatio = EUCTW_TYPICAL_DISTRIBUTION_RATIO;
michael@0: }
michael@0: 
michael@0: EUCKRDistributionAnalysis::EUCKRDistributionAnalysis()
michael@0: {
michael@0:   mCharToFreqOrder = EUCKRCharToFreqOrder;
michael@0:   mTableSize = mozilla::ArrayLength(EUCKRCharToFreqOrder);
michael@0:   mTypicalDistributionRatio = EUCKR_TYPICAL_DISTRIBUTION_RATIO;
michael@0: }
michael@0: 
michael@0: GB2312DistributionAnalysis::GB2312DistributionAnalysis()
michael@0: {
michael@0:   mCharToFreqOrder = GB2312CharToFreqOrder;
michael@0:   mTableSize = mozilla::ArrayLength(GB2312CharToFreqOrder);
michael@0:   mTypicalDistributionRatio = GB2312_TYPICAL_DISTRIBUTION_RATIO;
michael@0: }
michael@0: 
michael@0: Big5DistributionAnalysis::Big5DistributionAnalysis()
michael@0: {
michael@0:   mCharToFreqOrder = Big5CharToFreqOrder;
michael@0:   mTableSize = mozilla::ArrayLength(Big5CharToFreqOrder);
michael@0:   mTypicalDistributionRatio = BIG5_TYPICAL_DISTRIBUTION_RATIO;
michael@0: }
michael@0: 
michael@0: SJISDistributionAnalysis::SJISDistributionAnalysis()
michael@0: {
michael@0:   mCharToFreqOrder = JISCharToFreqOrder;
michael@0:   mTableSize = mozilla::ArrayLength(JISCharToFreqOrder);
michael@0:   mTypicalDistributionRatio = JIS_TYPICAL_DISTRIBUTION_RATIO;
michael@0: }
michael@0: 
michael@0: EUCJPDistributionAnalysis::EUCJPDistributionAnalysis()
michael@0: {
michael@0:   mCharToFreqOrder = JISCharToFreqOrder;
michael@0:   mTableSize = mozilla::ArrayLength(JISCharToFreqOrder);
michael@0:   mTypicalDistributionRatio = JIS_TYPICAL_DISTRIBUTION_RATIO;
michael@0: }
michael@0: