Line data    Source code

       1             : /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
       2             : /* This Source Code Form is subject to the terms of the Mozilla Public
       3             :  * License, v. 2.0. If a copy of the MPL was not distributed with this
       4             :  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
       5             : 
       6             : #include "CharDistribution.h"
       7             : 
       8             : #include "JISFreq.tab"
       9             : #include "mozilla/ArrayUtils.h"
      10             : 
      11             : #define SURE_YES 0.99f
      12             : #define SURE_NO  0.01f
      13             : 
      14             : //return confidence base on received data
      15           0 : float CharDistributionAnalysis::GetConfidence(void)
      16             : {
      17             :   //if we didn't receive any character in our consideration range, or the
      18             :   // number of frequent characters is below the minimum threshold, return
      19             :   // negative answer
      20           0 :   if (mTotalChars <= 0 || mFreqChars <= mDataThreshold)
      21           0 :     return SURE_NO;
      22             : 
      23           0 :   if (mTotalChars != mFreqChars) {
      24           0 :     float r = mFreqChars / ((mTotalChars - mFreqChars) * mTypicalDistributionRatio);
      25             : 
      26           0 :     if (r < SURE_YES)
      27           0 :       return r;
      28             :   }
      29             :   //normalize confidence, (we don't want to be 100% sure)
      30           0 :   return SURE_YES;
      31             : }
      32             : 
      33           0 : SJISDistributionAnalysis::SJISDistributionAnalysis()
      34             : {
      35           0 :   mCharToFreqOrder = JISCharToFreqOrder;
      36           0 :   mTableSize = mozilla::ArrayLength(JISCharToFreqOrder);
      37           0 :   mTypicalDistributionRatio = JIS_TYPICAL_DISTRIBUTION_RATIO;
      38           0 : }
      39             : 
      40           0 : EUCJPDistributionAnalysis::EUCJPDistributionAnalysis()
      41             : {
      42           0 :   mCharToFreqOrder = JISCharToFreqOrder;
      43           0 :   mTableSize = mozilla::ArrayLength(JISCharToFreqOrder);
      44           0 :   mTypicalDistributionRatio = JIS_TYPICAL_DISTRIBUTION_RATIO;
      45           0 : }
      46             :