From 2ddfea26f6d506c980477fa0fb7ba5dbdce896a8 Mon Sep 17 00:00:00 2001
From: "Rui Zhao (SPEECH)" <ruzhao@microsoft.com>
Date: Tue, 24 Sep 2019 15:56:55 -0700
Subject: [PATCH] force expand blank

---
 Source/SGDLib/SimpleOutputWriter.h | 54 ++++++++++++++++--------------
 1 file changed, 29 insertions(+), 25 deletions(-)

diff --git a/Source/SGDLib/SimpleOutputWriter.h b/Source/SGDLib/SimpleOutputWriter.h
index 10145d402..369a9b49e 100644
--- a/Source/SGDLib/SimpleOutputWriter.h
+++ b/Source/SGDLib/SimpleOutputWriter.h
@@ -441,7 +441,7 @@ public:
         return a.logP < b.logP;
     }
 
-    vector<pair<size_t, ElemType>> getTopN(Microsoft::MSR::CNTK::Matrix<ElemType>& prob, size_t N)
+    vector<pair<size_t, ElemType>> getTopN(Microsoft::MSR::CNTK::Matrix<ElemType>& prob, size_t N, size_t& blankid)
     {
         vector<pair<size_t, ElemType>> datapair;
         typedef vector<pair<size_t, ElemType>>::value_type ValueType;
@@ -453,6 +453,7 @@ public:
         nth_element(datapair.begin(), datapair.begin() + N, datapair.end(), [](ValueType const& x, ValueType const& y) -> bool {
             return y.second < x.second;
         });
+        datapair.push_back(ValueType(blankid, probdata[blankid]));
         delete probdata;
         return datapair;
     }
@@ -656,7 +657,7 @@ public:
 
                     //sumofENandDE.Print("sum");
                     //sort log posterior and get best N labels
-                    vector<pair<size_t, ElemType>> topN = getTopN(decodeOutput, expandBeam);
+                    vector<pair<size_t, ElemType>> topN = getTopN(decodeOutput, expandBeam, blankId);
                     /*ElemType* logP = decodeOutput.CopyToArray();
                     std::priority_queue<std::pair<double, int>> q;
                     int iLabel;
@@ -681,38 +682,41 @@ public:
                         CurSequences.push_back(seqK);
                         q.pop();
                     }*/
+					//expand blank
+                    Sequence seqK = newSeq(tempSeq, deviceid);
+                    ElemType newlogP = topN[vocabSize].second + tempSeq.logP;
+                    seqK.logP = newlogP;
+                    bool existseq = false;
+                    for (auto itseq = nextSequences.begin(); itseq != nextSequences.end(); itseq++)
+                    //for (Sequence seqP : keyNextSequences)  //does not work
+                    {
+                        //merge the score with same sequence
+                        if (seqK.labelseq == itseq->labelseq)
+                        {
+                            existseq = true;
+                            itseq->logP = decodeOutput.LogAdd(seqK.logP, itseq->logP);
+                            //itseq->lengthwithblank = (seqK.lengthwithblank + itseq->lengthwithblank) / 2;
+                            break;
+                        }
+                    }
+                    if (!existseq)
+                    {
+                        nextSequences.push_back(seqK);
+                    }
+					
                     int iLabel;
                     for (iLabel = 0; iLabel < expandBeam; iLabel++)
                     {
 
-                        Sequence seqK = newSeq(tempSeq, deviceid);
-                        ElemType newlogP = topN[iLabel].second + tempSeq.logP;
+                        seqK = newSeq(tempSeq, deviceid);
+                        newlogP = topN[iLabel].second + tempSeq.logP;
                         seqK.logP = newlogP;
 
-                        if (topN[iLabel].first == blankId)
+                        if (topN[iLabel].first != blankId)
                         {
-                            bool existseq = false;
-                            for (auto itseq = nextSequences.begin(); itseq != nextSequences.end(); itseq++)
-                            //for (Sequence seqP : keyNextSequences)
-                            {
-                                //merge the score with same sequence
-                                if (seqK.labelseq == itseq->labelseq)
-                                {
-                                    existseq = true;
-                                    itseq->logP = decodeOutput.LogAdd(seqK.logP, itseq->logP);
-                                    //itseq->lengthwithblank = (seqK.lengthwithblank + itseq->lengthwithblank) / 2;
-                                    break;
-                                }
-                            }
-                            if (!existseq)
-                            {
-                                nextSequences.push_back(seqK);
-                            }
-                            //nextSequences.push_back(seqK);
-                            continue;
-                        }
                         extendSeq(seqK, topN[iLabel].first, newlogP);
                         CurSequences.push_back(seqK);
+}
                     }
                     vector<pair<size_t, ElemType>>().swap(topN);
                     //delete topN;