public double getPossibility(int key, int prev, int cur) {
double result = 0;
int curIndex = Utility.binarySearch(cur, symbolTable);
int prevIndex = Utility.binarySearch(prev, symbolTable);
TagContext tc = getItem(key);
// return a lower value, not 0 to prevent data sparse
if (tc == null
|| curIndex == -1
|| prevIndex == -1
|| tc.getContextArray()[prevIndex][curIndex] == 0
|| tc.getTagFreq()[prevIndex] == 0) return 0.000001;
int prevCurConFreq = tc.getContextArray()[prevIndex][curIndex];
int prevFreq = tc.getTagFreq()[prevIndex];
// 0.9 and 0.1 is a value based experience
result = 0.9 * prevCurConFreq;
result /= prevFreq;
result += 0.1 * prevFreq / tc.getTotalFreq();
return result;
}
public int getFreq(int key, int symbol) {
TagContext tc = getItem(key);
if (tc == null) return 0;
int index = Utility.binarySearch(symbol, symbolTable);
if (index == -1) // error finding the symbol
return 0;
// Add the frequency
int frequency = 0;
if (tc.getTagFreq() != null) frequency = tc.getTagFreq()[index];
return frequency;
}