//Calculate the probability of given text
public LMResult GetSentProb(string strText, int order)
{
LMResult LMRst = new LMResult();
int calcWordNum = 0;
//Append EOS into the sentence
strText = strText + " EOS";
string[] items = strText.Split();
int wordNum = items.Length;
for (int i = 0; i < wordNum; i++)
{
string words = String.Join(" ", items, 0, i + 1);
// calc prob of ngram[j,i]
int start = (i > order - 1) ? (i - order + 1) : 0;
double prob = 0.0;
if (lm_ngram_prob(words, start, i, ref prob) == 0)
{
LMRst.logProb += prob;
}
else
{
LMRst.oovs++;
}
calcWordNum++;
}
int denom = calcWordNum - LMRst.oovs;
LMRst.perplexity = log2prob(-LMRst.logProb / denom);
return(LMRst);
}
public List <SynResult> GetSynonym(string strQuery, int begin, int len)
{
List <SynResult> synRstList = new List <SynResult>();
//Get candidate synonym term
string strTerm = strQuery.Substring(begin, len);
//Word breaking strQuery
string strWBQuery = WordSegment(strQuery);
//Get sentence probability by language model
//Call RNN language model
RnnLMResult lmResult_rnn = lmDecoder_rnn.GetSentProb(strWBQuery);
//Call Ngram language model
LMDecoder.LMResult lmResult = lmDecoder.GetSentProb(strWBQuery, lmOrder);
SynResult synRst = new SynResult();
synRst.strTerm = strTerm;
synRst.lmScore = (int)(lmResult.perplexity / 1.0);
synRst.lmScore_rnn = (int)(lmResult_rnn.perplexity / 1.0);
synRst.llr = -1.0;
synRstList.Add(synRst);
if (synPair.ContainsKey(strTerm) == false)
{
return(synRstList);
}
string strLCtx = strQuery.Substring(0, begin);
string strRCtx = strQuery.Substring(begin + len);
foreach (SynContextSet ctx in synPair[strTerm])
{
//Replace the term with its synonym term
string strText = strLCtx + ctx.strTerm + strRCtx;
//Word breaking strQuery
strWBQuery = WordSegment(strText);
//Get sentence probability by language model
//Call RNN language model
lmResult_rnn = lmDecoder_rnn.GetSentProb(strWBQuery);
//Call ngram language model
lmResult = lmDecoder.GetSentProb(strWBQuery, lmOrder);
synRst = new SynResult();
synRst.strTerm = ctx.strTerm;
synRst.lmScore = (int)(lmResult.perplexity / 1.0);
synRst.lmScore_rnn = (int)(lmResult_rnn.perplexity / 1.0);
synRst.llr = ctx.llr;
synRstList.Add(synRst);
}
synRstList.Sort(CompareLMResult);
return(synRstList);
}
