new code of t2t trainer

source/sample/fnnlm/FNNLM.cpp

@@ -580,7 +580,7 @@ void Update(FNNModel &model, FNNModel &grad, float epsilon, bool isNodeGrad)
 get prediction probabilites of the gold words
 >> output - output probabilities
 >> gold - gold standard
->> 
+>> wordPobs - probability of each word
 << return - probability of the batch
 */
 float GetProb(XTensor &output, XTensor &gold, XTensor * wordProbs)

source/sample/transformer/T2TTrainer.cpp

@@ -19,8 +19,11 @@
  * $Created by: XIAO Tong (xiaotong@mail.neu.edu.cn) 2018-08-02
  */
 
+#include <math.h>
 #include "T2TTrainer.h"
 #include "T2TUtility.h"
+#include "../../tensor/XUtility.h"
+#include "../../tensor/core/CHeader.h"
 
 namespace transformer
 {
@@ -52,6 +55,7 @@ void T2TTrainer::Init(int argc, const char ** argv)
     LoadParamInt(argc, argv, "wbatch", &wBatchSize, 1);
     LoadParamInt(argc, argv, "nepoch", &nepoch, 1);
     LoadParamInt(argc, argv, "nstep", &nstep, 1);
+    LoadParamBool(argc, argv, "sorted", &isLenSorted, false);
 
     int maxUnitInBuf;
     LoadParamInt(argc, argv, "bufsize", &maxUnitInBuf, 20000);
@@ -67,6 +71,64 @@ train the model
 */
 void T2TTrainer::Train(const char * fn, T2TModel * model)
 {
+    int epoch = 0;
+    int step = 0;
+    int wc = 0;
+    int wordCount = 0;
+    int wordCountTotal = 0;
+    bool isEnd = false;
+    float loss = 0;
+    
+    double startT = GetClockSec();
+    
+    for(epoch = 0; epoch < nepoch; epoch++){
+        
+        FILE * file = fopen(fn, "rb");
+        CheckNTErrors(file, "cannot open training file!");
+        
+        wordCount = 0;
+        
+        /* batch of input sequences */
+        XTensor batch;
+        
+        /* output probabilities */
+        XTensor output;
+        
+        while(LoadBatch(file, &batch, 1, vSize, sBatchSize, wBatchSize, isLenSorted, wc)){
+            
+            /* make the network */
+            model->Make(&batch, &output);
+            
+            /* TODO: update the model!!!! */
+            
+            /* get probabilities */
+            float prob = GetProb(&output, &batch, NULL);
+            
+            loss += -prob;
+            wordCount += wc;
+            wordCountTotal += wc;
+            
+            if(++step >= nstep){
+                isEnd = true;
+                break;
+            }
+            
+            if (step % 100 == 0) {
+                double elapsed = GetClockSec() - startT;
+                XPRINT5(0, stderr, "[INFO] elapsed=%.1fs, step=%d, epoch=%d, ngram=%d, ppl=%.3f\n",
+                        elapsed, step, epoch + 1, wordCountTotal, exp(loss / wordCount));
+            }
+        }
+        
+        fclose(file);
+    }
+    
+    double elapsed = GetClockSec() - startT;
+    
+    XPRINT5(0, stderr, "[INFO] elapsed=%.1fs, step=%d, epoch=%d, ngram=%d, ppl=%.3f\n",
+            elapsed, step, epoch, wordCountTotal, exp(loss / wordCount));
+    XPRINT3(0, stderr, "[INFO] training finished (took %.1fs, step=%d and epoch=%d)\n",
+            elapsed, step, epoch);
 }
 
 char line[MAX_SEQUENCE_LENGTH];
@@ -126,10 +188,7 @@ int T2TTrainer::LoadBuf(FILE * file)
         wordCount += wNum;
         lineCount++;
 
-        if(wordCount >= wBatchSize)
-            break;
-        
-        if(lineCount >= sBatchSize)
+        if(wordCount >= wBatchSize || lineCount >= sBatchSize)
             break;
     }
 
@@ -148,8 +207,9 @@ load a batch of sequences
 >> sBatch - batch size of sequences
 >> wBatch - batch size of words
 >> isSorted - indicates whether the sequences are sorted by length
+>> wCount - word count
 */
-int T2TTrainer::LoadBatch(FILE * file, XTensor * batch, int step, int vs, int sBatch, int wBatch, bool isSorted)
+int T2TTrainer::LoadBatch(FILE * file, XTensor * batch, int step, int vs, int sBatch, int wBatch, bool isSorted, int &wCount)
 {
     if(nextSeq >= nseqBuf)
         LoadBuf(file);
@@ -182,14 +242,55 @@ int T2TTrainer::LoadBatch(FILE * file, XTensor * batch, int step, int vs, int sB
 
         batch->SetZeroAll();
 
+        /* this might be slow on GPUs :( */
         for(int s = seq; s < seq + sc; s++){
             for(int w = 0; w < seqLen[s]; w++){
                 batch->Set3D(1.0F, s - seq, w, buf[seqOffset[s] + w]);
+                wCount++;
             }
         }
     }
 
     return sc;
 }
+    
+/*
+get word probabilities for a batch of sequences
+>> output - word distribution for each position
+>> gold - gold standard
+>> wordProbs - word probability for gold prediction
+*/
+float T2TTrainer::GetProb(XTensor * output, XTensor * gold, XTensor * wordProbs)
+{
+    XTensor probs;
+    InitTensor(&probs, output);
+    
+    /* probs[i,j] = output[i,j] * gold[i,j] */
+    _Multiply(output, gold, &probs);
+    
+    /* probability of each word */
+    XTensor wprobs;
+    InitTensor1D(&wprobs, output->unitNum/output->GetDim(-1), X_FLOAT, output->devID, output->mem);
+    
+    int dims[2] = {output->unitNum/output->GetDim(-1), output->GetDim(-1)};
+    probs.Reshape(2, dims);
+    _ReduceSum(&probs, &wprobs, 1);
+    
+    if(wordProbs != NULL)
+        _CopyValues(&wprobs, wordProbs);
+    
+    /* reshape the tensor to fit it into the reduce procedure
+     TODO: XTensor supports scalars */
+    dims[0] = 1;
+    dims[1] = probs.unitNum;
+    probs.Reshape(2, dims);
+    
+    /* probability for the batch */
+    XTensor result;
+    InitTensor1D(&result, 1, X_FLOAT, output->devID, output->mem);
+    _ReduceSum(&probs, &result, 1);
+    
+    return result.Get1D(0);
+}
 
-}
\ No newline at end of file
+}

source/sample/transformer/T2TTrainer.h

@@ -57,6 +57,9 @@ public:
 
     /* offset for next sequence in the buffer */
     int nextSeq;
+    
+    /* indicates whether the sequence is sorted by length */
+    bool isLenSorted;
 
     /* vocabulary size of the source side */
     int vSize;
@@ -93,10 +96,13 @@ public:
     int LoadBuf(FILE * file);
 
     /* load a batch of sequences */
-    int LoadBatch(FILE * file, XTensor * batch, int step, int vs, int sBatch, int wBatch, bool isSorted); 
+    int LoadBatch(FILE * file, XTensor * batch, int step, int vs, int sBatch, int wBatch, bool isSorted, int &wCount);
+    
+    /* get word probabilities for a batch of sequences */
+    float GetProb(XTensor * output, XTensor * gold, XTensor * wordProbs);
 };
 
 
 }
 
-#endif
\ No newline at end of file
+#endif