diff --git a/Analyser.cpp b/Analyser.cpp
index 693fee6..2df0f2e 100644
--- a/Analyser.cpp
+++ b/Analyser.cpp
@@ -11,6 +11,9 @@ Analyzer::Analyzer(Digitizer ** digi, unsigned int nDigi, QMainWindow * parent )
   setWindowTitle("Online Analyzer");
   setGeometry(0, 0, 1000, 800);  
 
+  influx = nullptr;
+  dataBaseName = "";
+
   mb = new MultiBuilder(digi, nDigi);
 
   buildTimerThread = new TimingThread(this);
@@ -28,7 +31,7 @@ Analyzer::Analyzer(Digitizer ** digi, unsigned int nDigi, QMainWindow * parent )
 }
 
 Analyzer::~Analyzer(){
-
+  delete influx;
   delete mb;
 }
 
@@ -51,15 +54,15 @@ void Analyzer::StopThread(){
 
 
 
-void Analyzer::BuildEvents(){
+void Analyzer::BuildEvents(bool verbose){
 
   unsigned int nData = mb->GetNumOfDigitizer();
   std::vector<int> idList = mb->GetDigiIDList();
   for( unsigned int i = 0; i < nData; i++ ) digiMTX[idList[i]].lock();
   if( isBuildBackward ){
-    mb->BuildEventsBackWard(0);
+    mb->BuildEventsBackWard(maxNumEventBuilt, verbose);
   }else{
-    mb->BuildEvents(0, 0, 0);
+    mb->BuildEvents(0, 0, verbose);
   }
   for( unsigned int i = 0; i < nData; i++ ) digiMTX[idList[i]].unlock();
 
diff --git a/Analyser.h b/Analyser.h
index 68254bb..f6fb2c5 100644
--- a/Analyser.h
+++ b/Analyser.h
@@ -15,8 +15,8 @@
 #include "ClassDigitizer.h"
 #include "CustomThreads.h"
 #include "CustomWidgets.h"
-//#include "OnlineEventBuilder.h"
 #include "MultiBuilder.h"
+#include "influxdb.h"
 
 /**************************************
 
@@ -46,7 +46,7 @@ public:
   MultiBuilder * GetEventBuilder() { return mb;}
 
   void RedefineEventBuilder(std::vector<int> idList);
-  void SetBackwardBuild(bool TF) { isBuildBackward = TF;}
+  void SetBackwardBuild(bool TF, int maxNumEvent = 100) { isBuildBackward = TF; maxNumEventBuilt = maxNumEvent;}
 
 public slots:
   void StartThread();
@@ -58,9 +58,12 @@ private slots:
 
 protected:
   QGridLayout * layout;
-  void BuildEvents();
+  void BuildEvents(bool verbose = false);
   void SetUpdateTimeInSec(double sec = 1.0) {waitTimeinSec = sec; buildTimerThread->SetWaitTimeinSec(waitTimeinSec);}
 
+  InfluxDB * influx;
+  std::string dataBaseName;
+
 private:
   Digitizer ** digi;
   unsigned short nDigi;
@@ -69,7 +72,9 @@ private:
 
   MultiBuilder * mb;
   bool isBuildBackward;
+  int maxNumEventBuilt;
   TimingThread * buildTimerThread;
 
+
 };
 #endif
\ No newline at end of file
diff --git a/ClassData.h b/ClassData.h
index 515ca06..6a481d7 100644
--- a/ClassData.h
+++ b/ClassData.h
@@ -23,7 +23,7 @@ class Data{
     int DPPType;
     std::string DPPTypeStr;
     unsigned short boardSN;
-    float ch2ns;  /// only use in TriggerRate calculation
+    float tick2ns;  /// only use in TriggerRate calculation
     
     unsigned int nByte;               /// number of byte from read buffer
     uint32_t AllocatedSize;      
@@ -42,7 +42,7 @@ class Data{
     int                DataIndex[MaxNChannels];
 
     unsigned long long Timestamp[MaxNChannels][MaxNData]; /// 47 bit
-    unsigned short     fineTime[MaxNChannels][MaxNData];  /// 10 bits, in unit of ch2ns / 1000 = ps
+    unsigned short     fineTime[MaxNChannels][MaxNData];  /// 10 bits, in unit of tick2ns / 1000 = ps
     unsigned short     Energy[MaxNChannels][MaxNData];   /// 15 bit
     unsigned short     Energy2[MaxNChannels][MaxNData];  /// 15 bit, in PSD, Energy = Qshort, Energy2 = Qlong
     bool               PileUp[MaxNChannels][MaxNData];   /// pile up flag
@@ -113,7 +113,7 @@ class Data{
 //==========================================
 
 inline Data::Data(){
-  ch2ns = 2.0;
+  tick2ns = 2.0;
   boardSN = 0;
   DPPType = V1730_DPP_PHA_CODE;
   DPPTypeStr = "";
@@ -414,7 +414,7 @@ inline void Data::DecodeBuffer(bool fastDecode, int verbose){
       //printf("%d %d| %d %d \n", DataIndex[ch], NumEventsDecoded[ch], indexStart, DataIndex[ch] );
 
       unsigned long long dTime = Timestamp[ch][DataIndex[ch]] - Timestamp[ch][indexStart]; 
-      double sec =  dTime * ch2ns / 1e9;
+      double sec =  dTime * tick2ns / 1e9;
 
       TriggerRate[ch] = NumEventsDecoded[ch]/sec;
       NonPileUpRate[ch] = NumNonPileUpDecoded[ch]/sec;
@@ -430,9 +430,9 @@ inline void Data::DecodeBuffer(bool fastDecode, int verbose){
       
       if( calIndexes[ch][0] > -1 && calIndexes[ch][1] > -1 && nEvent > 10 ){
           unsigned long long dTime = Timestamp[ch][calIndexes[ch][1]] - Timestamp[ch][calIndexes[ch][0]];
-          double sec = dTime * ch2ns / 1e9;
+          double sec = dTime * tick2ns / 1e9;
         
-          //printf(" %10llu  %10llu, %f = %f sec, rate = %f \n", Timestamp[ch][calIndexes[ch][0]], Timestamp[ch][calIndexes[ch][1]], ch2ns, sec, nEvent / sec);
+          //printf(" %10llu  %10llu, %f = %f sec, rate = %f \n", Timestamp[ch][calIndexes[ch][0]], Timestamp[ch][calIndexes[ch][1]], tick2ns, sec, nEvent / sec);
 
           TriggerRate[ch] = nEvent / sec;
 
diff --git a/ClassDigitizer.cpp b/ClassDigitizer.cpp
index 3ea6b25..aae516e 100644
--- a/ClassDigitizer.cpp
+++ b/ClassDigitizer.cpp
@@ -25,7 +25,7 @@ void Digitizer::Initalization(){
   ADCbits  = 1;
   DPPType = 0;
   ADCFullSize = 0;
-  ch2ns = 0; 
+  tick2ns = 0; 
   BoardInfo = {};
 
   channelMask = 0xFFFF;
@@ -59,7 +59,7 @@ void Digitizer::Reset(){
 
 void Digitizer::PrintBoard (){
   printf("Connected to Model %s with handle %d using %s\n", BoardInfo.ModelName, handle, LinkType == CAEN_DGTZ_USB ? "USB" : "Optical Link");
-  printf("Sampling rate : %.0f MHz = %.1f ns \n", 1000/ch2ns, ch2ns);
+  printf("Sampling rate : %.0f MHz = %.1f ns \n", 1000/tick2ns, tick2ns);
   printf("Number of Channels : %d = 0x%X\n", NChannel, channelMask);
   printf("SerialNumber :\e[1m\e[33m %d\e[0m\n", BoardInfo.SerialNumber);
   printf("DPPType : %d (%s)\n", DPPType, GetDPPString().c_str());
@@ -103,11 +103,11 @@ int Digitizer::OpenDigitizer(int boardID, int portID, bool program, bool verbose
       NChannel = BoardInfo.Channels;
       channelMask = pow(2, NChannel)-1;
       switch(BoardInfo.Model){
-            case CAEN_DGTZ_V1730: ch2ns = 2.0; break; ///ns -> 500 MSamples/s
-            case CAEN_DGTZ_V1725: ch2ns = 4.0; break; ///ns -> 250 MSamples/s
-            default : ch2ns = 4.0; break;
+            case CAEN_DGTZ_V1730: tick2ns = 2.0; break; ///ns -> 500 MSamples/s
+            case CAEN_DGTZ_V1725: tick2ns = 4.0; break; ///ns -> 250 MSamples/s
+            default : tick2ns = 4.0; break;
       }
-      data->ch2ns = ch2ns;
+      data->tick2ns = tick2ns;
       data->boardSN = BoardInfo.SerialNumber;
       ADCbits = BoardInfo.ADC_NBits;
       ADCFullSize = (unsigned int)( pow(2, ADCbits) -1 );
@@ -739,8 +739,8 @@ int Digitizer::LoadSettingBinaryToMemory(std::string fileName){
       if( dummy != 0 ) printf("reach the end of file (read %ld).\n", dummy);
       
       uint32_t boardInfo = GetSettingFromMemory(DPP::BoardInfo_R);
-      if( (boardInfo & 0xFF) == 0x0E ) ch2ns = 4.0;
-      if( (boardInfo & 0xFF) == 0x0B ) ch2ns = 2.0;
+      if( (boardInfo & 0xFF) == 0x0E ) tick2ns = 4.0;
+      if( (boardInfo & 0xFF) == 0x0B ) tick2ns = 2.0;
 
       ///Should seperate file<->memory, memory<->board
       ///ProgramSettingsToBoard(); /// do nothing if not connected.
diff --git a/ClassDigitizer.h b/ClassDigitizer.h
index 255e27b..3b74dcd 100644
--- a/ClassDigitizer.h
+++ b/ClassDigitizer.h
@@ -31,7 +31,7 @@ class Digitizer{
     int                   ADCbits;       /// ADC bit
     int                   DPPType;       /// DPP verion
     unsigned int          ADCFullSize;   /// pow(2, ADCbits) - 1
-    float                 ch2ns;         /// channel to ns
+    float                 tick2ns;         /// channel to ns
     CAEN_DGTZ_BoardInfo_t BoardInfo;
     
     //^----- adjustable parameters
@@ -105,7 +105,7 @@ class Digitizer{
     int         GetSerialNumber()            const {return BoardInfo.SerialNumber;}
     int         GetChannelMask()             { channelMask = GetSettingFromMemory(DPP::ChannelEnableMask); return channelMask;}
     bool        GetChannelOnOff(unsigned ch) { channelMask = GetSettingFromMemory(DPP::ChannelEnableMask); return (channelMask & ( 1 << ch) );} 
-    float       GetCh2ns()                   const {return ch2ns;}
+    float       GetTick2ns()                   const {return tick2ns;}
     int         GetNChannels()               const {return NChannel;}
     int         GetHandle()                  const {return handle;}
     int         GetDPPType()                 const {return DPPType;}
diff --git a/DigiSettingsPanel.cpp b/DigiSettingsPanel.cpp
index 526809a..a43e887 100644
--- a/DigiSettingsPanel.cpp
+++ b/DigiSettingsPanel.cpp
@@ -74,7 +74,7 @@ DigiSettingsPanel::DigiSettingsPanel(Digitizer ** digi, unsigned int nDigi, QStr
 
       SetUpInfo(  "S/N No. ", std::to_string(digi[ID]->GetSerialNumber()), infoLayout[ID], 1, 0);
       SetUpInfo(  "No. Ch. ", std::to_string(digi[ID]->GetNChannels()), infoLayout[ID], 1, 2);
-      SetUpInfo("Sampling Rate ", std::to_string((int) digi[ID]->GetCh2ns()) + " ns = " + std::to_string( (int) (1000/digi[ID]->GetCh2ns())) + " MHz" , infoLayout[ID], 1, 4);
+      SetUpInfo("Sampling Rate ", std::to_string((int) digi[ID]->GetTick2ns()) + " ns = " + std::to_string( (int) (1000/digi[ID]->GetTick2ns())) + " MHz" , infoLayout[ID], 1, 4);
 
       SetUpInfo("ADC bit ", std::to_string(digi[ID]->GetADCBits()), infoLayout[ID], 2, 0);
       SetUpInfo("ROC version ", digi[ID]->GetROCVersion(), infoLayout[ID], 2, 2);
@@ -733,8 +733,8 @@ void DigiSettingsPanel::SetUpSpinBox(RSpinBox * &sb, QString label, QGridLayout
     sb->setSingleStep(1);
     sb->setMaximum(para.GetMaxBit());
   }else{
-    sb->setMaximum(para.GetMaxBit() * para.GetPartialStep() * digi[ID]->GetCh2ns());
-    sb->setSingleStep(para.GetPartialStep() * digi[ID]->GetCh2ns());
+    sb->setMaximum(para.GetMaxBit() * para.GetPartialStep() * digi[ID]->GetTick2ns());
+    sb->setSingleStep(para.GetPartialStep() * digi[ID]->GetTick2ns());
   }
 
   if( para == DPP::DPPAlgorithmControl ) {
@@ -770,7 +770,7 @@ void DigiSettingsPanel::SetUpSpinBox(RSpinBox * &sb, QString label, QGridLayout
     }
 
     if( para == DPP::PSD::CFDSetting ){
-      digi[ID]->SetBits(para, DPP::PSD::Bit_CFDSetting::CFDDealy, sb->value()/digi[ID]->GetCh2ns(), chID);
+      digi[ID]->SetBits(para, DPP::PSD::Bit_CFDSetting::CFDDealy, sb->value()/digi[ID]->GetTick2ns(), chID);
       UpdatePanelFromMemory();
       emit UpdateOtherPanels();
       return;
@@ -783,7 +783,7 @@ void DigiSettingsPanel::SetUpSpinBox(RSpinBox * &sb, QString label, QGridLayout
       return;
     }
 
-    uint32_t bit = para.GetPartialStep() == -1 ? sb->value() : sb->value() / para.GetPartialStep() / digi[ID]->GetCh2ns();
+    uint32_t bit = para.GetPartialStep() == -1 ? sb->value() : sb->value() / para.GetPartialStep() / digi[ID]->GetTick2ns();
 
     digi[ID]->WriteRegister(para, bit, chID);
     if( para.IsCoupled() == true  && chID >= 0 ) digi[ID]->WriteRegister(para, bit, chID%2 == 0 ? chID + 1 : chID - 1);
@@ -964,8 +964,8 @@ void DigiSettingsPanel::SetUpGlobalTriggerMaskAndFrontPanelMask(QGridLayout * &
 
   sbGlbMajCoinWin[ID] = new RSpinBox(this);
   sbGlbMajCoinWin[ID]->setMinimum(0);
-  sbGlbMajCoinWin[ID]->setMaximum(0xF * 4 * digi[ID]->GetCh2ns() );
-  sbGlbMajCoinWin[ID]->setSingleStep(4 * digi[ID]->GetCh2ns());
+  sbGlbMajCoinWin[ID]->setMaximum(0xF * 4 * digi[ID]->GetTick2ns() );
+  sbGlbMajCoinWin[ID]->setSingleStep(4 * digi[ID]->GetTick2ns());
   maskLayout->addWidget(sbGlbMajCoinWin[ID], 1, 10);
   connect(sbGlbMajCoinWin[ID], &RSpinBox::valueChanged, this, [=](){
     if( !enableSignalSlot ) return;
@@ -982,7 +982,7 @@ void DigiSettingsPanel::SetUpGlobalTriggerMaskAndFrontPanelMask(QGridLayout * &
     }
 
     sbGlbMajCoinWin[ID]->setStyleSheet("");
-    digi[ID]->SetBits(DPP::GlobalTriggerMask, DPP::Bit_GlobalTriggerMask::MajorCoinWin, sbGlbMajCoinWin[ID]->value() / 4 / digi[ID]->GetCh2ns(), -1);
+    digi[ID]->SetBits(DPP::GlobalTriggerMask, DPP::Bit_GlobalTriggerMask::MajorCoinWin, sbGlbMajCoinWin[ID]->value() / 4 / digi[ID]->GetTick2ns(), -1);
   });
 
   //*============================================
@@ -2581,7 +2581,7 @@ void DigiSettingsPanel::UpdatePanelFromMemory(){
 //&###########################################################
 void DigiSettingsPanel::UpdateSpinBox(RSpinBox * &sb, Reg para, int ch){
 
-  int ch2ns = digi[ID]->GetCh2ns();
+  int tick2ns = digi[ID]->GetTick2ns();
   int pStep = para.GetPartialStep();
 
   uint32_t value = digi[ID]->GetSettingFromMemory(para, ch);
@@ -2593,7 +2593,7 @@ void DigiSettingsPanel::UpdateSpinBox(RSpinBox * &sb, Reg para, int ch){
   }
 
   if( para == DPP::PSD::CFDSetting ){
-    sb->setValue( ( value & DPP::PSD::CFDSetting.GetMaxBit() ) * ch2ns );
+    sb->setValue( ( value & DPP::PSD::CFDSetting.GetMaxBit() ) * tick2ns );
     return;
   }
 
@@ -2602,9 +2602,9 @@ void DigiSettingsPanel::UpdateSpinBox(RSpinBox * &sb, Reg para, int ch){
     return;
   }
 
-  sb->setValue( pStep > 0 ? value * pStep * ch2ns : value);
+  sb->setValue( pStep > 0 ? value * pStep * tick2ns : value);
 
-  //printf("%d, %s | %d %d %u, %f\n", para.GetNameChar(), ch, ch2ns, pStep, value, sb->value());
+  //printf("%d, %s | %d %d %u, %f\n", para.GetNameChar(), ch, tick2ns, pStep, value, sb->value());
 
 }
 
diff --git a/Histogram2D.h b/Histogram2D.h
index e9bfd8b..97a790e 100644
--- a/Histogram2D.h
+++ b/Histogram2D.h
@@ -136,143 +136,7 @@ public:
       }
 
       //^================= right click
-      if (event->button() == Qt::RightButton) {
-        usingMenu = true;
-        setSelectionRectMode(QCP::SelectionRectMode::srmNone);
-
-        QMenu *menu = new QMenu(this);
-        menu->setAttribute(Qt::WA_DeleteOnClose);
-
-        QAction * a1 = menu->addAction("UnZoom");
-        QAction * a2 = menu->addAction("Clear hist.");
-        QAction * a3 = menu->addAction("Toggle Stat.");
-        QAction * a4 = menu->addAction("Rebin (clear histogram)");
-        QAction * a5 = menu->addAction("Create a Cut");
-        if( numCut > 0 ) {
-          menu->addSeparator();
-          menu->addAction("Add/Edit names to Cuts");
-          menu->addAction("Clear all Cuts");
-        }
-        for( int i = 0; i < cutList.size(); i++){
-          if( cutList[i].isEmpty()) continue;
-          QString haha = "";
-          menu->addAction("Delete " + cutNameList[i] + " ["+ colorCycle[cutIDList[i]%colorCycle.count()].second+"]");
-        }
-
-        QAction *selectedAction = menu->exec(event->globalPosition().toPoint());
-
-        if( selectedAction == a1 ){
-          xAxis->setRangeLower(xMin);
-          xAxis->setRangeUpper(xMax);
-          yAxis->setRangeLower(yMin);
-          yAxis->setRangeUpper(yMax);
-          replot();
-          usingMenu = false;
-          return;
-        }
-
-        if( selectedAction == a2 ) {
-          Clear();
-          usingMenu = false;
-          return;
-        }
-
-        if( selectedAction == a3 ){
-          for( int i = 0; i < 3; i ++ ){
-            for( int j = 0; j < 3; j ++ ){
-              box[i][j]->setVisible( !box[i][j]->visible());
-              txt[i][j]->setVisible( !txt[i][j]->visible());
-            }
-          }
-          replot();
-          usingMenu = false;
-          return;
-        }
-
-        if( selectedAction == a4){
-          rightMouseClickRebin();
-          usingMenu = false;
-          return;
-        }
-
-        if( selectedAction == a5 ){
-          tempCut.clear();
-          tempCutID ++;
-          isDrawCut= true;
-          usingMenu = false;
-          numCut ++;
-          return;
-        }
-
-        if( selectedAction && numCut > 0 && selectedAction->text().contains("Delete ") ){
-
-          QString haha = selectedAction->text();
-          int index1 = haha.indexOf("-");
-          int index2 = haha.indexOf("[");
-          int cutID = haha.mid(index1+1, index2-index1-1).remove(' ').toInt();
-          
-          removeItem(cutTextIDList[cutID]);
-          removePlottable(plottableIDList[cutID]);
-          replot();
-
-          numCut --;
-          cutList[cutID].clear();
-          cutIDList[cutID] = -1;
-          cutTextIDList[cutID] = -1;
-          plottableIDList[cutID] = -1;
-          cutNameList[cutID] = "";
-          cutEntryList[cutID] = -1;
-
-          for( int i = cutID + 1; i < cutTextIDList.count() ; i++){
-              cutTextIDList[i] --;
-              plottableIDList[i] --;
-          }
-
-          if( numCut == 0 ){
-            tempCutID = -1;
-            lastPlottableID = -1;
-            cutList.clear();
-            cutIDList.clear();
-            cutTextIDList.clear();
-            plottableIDList.clear();
-            cutNameList.clear();
-            cutEntryList.clear();
-          }
-          return;
-        }
-
-        if( selectedAction && numCut > 0 && selectedAction->text().contains("Clear all Cuts") ){
-          ClearAllCuts();
-          return;
-        }
-
-        if( selectedAction && numCut > 0 && selectedAction->text().contains("Add/Edit names to Cuts") ){
-          
-          QDialog dialog(this);
-          dialog.setWindowTitle("Add/Edit name of cuts ");
-
-          QFormLayout layout(&dialog);
-
-          for(int i = 0; i < cutTextIDList.count(); i++){
-            if( cutTextIDList[i] < 0 ) continue;
-            QLineEdit * le = new QLineEdit(&dialog);
-            layout.addRow(colorCycle[i%colorCycle.count()].second, le);
-            le->setText( cutNameList[i] );
-            connect(le, &QLineEdit::textChanged, this, [=](){
-              le->setStyleSheet("color : blue;");
-            });
-            connect(le, &QLineEdit::returnPressed, this, [=](){
-              le->setStyleSheet("");
-              cutNameList[i] = le->text();
-              ((QCPItemText *) this->item(cutTextIDList[i]))->setText(le->text());
-              replot();
-            });
-          }
-          dialog.exec();
-          return;
-        }
-
-      }///================= end of right click
+      if (event->button() == Qt::RightButton) rightMouseClickMenu(event);
     });
 
     //connect( this, &QCustomPlot::mouseDoubleClick, this, [=](QMouseEvent *event){
@@ -310,134 +174,26 @@ public:
 
     connect(this, &QCustomPlot::mouseRelease, this, [=](){
 
-
     });
   }
 
   //^===================================
 
-  void Rebin(int xbin, double xmin, double xmax, int ybin, double ymin, double ymax){
-    xMin = xmin;
-    xMax = xmax;
-    yMin = ymin;
-    yMax = ymax;
-    xBin = xbin;
-    yBin = ybin;
+  void Rebin(int xbin, double xmin, double xmax, int ybin, double ymin, double ymax);
 
-    colorMap->data()->clear();
-    colorMap->data()->setSize(xBin, yBin);
-    colorMap->data()->setRange(QCPRange(xMin, xMax), QCPRange(yMin, yMax));
+  void UpdatePlot(){ colorMap->rescaleDataRange(); replot(); }
 
-    for( int i = 0; i < 3; i ++){
-      for( int j = 0; j < 3; j ++){
-        entry[i][j] = 0;
-        if( txt[i][j] ) txt[i][j]->setText("0");
-      }
-    }
+  void Clear(); // Clear Data and histrogram
 
-  }
+  void Fill(double x, double y);
 
-  void UpdatePlot(){
-    colorMap->rescaleDataRange();
-    //rescaleAxes();
-    replot();
-  }
-
-  void Clear(){
-    
-    for( int i = 0; i < 3; i ++){
-      for( int j = 0; j < 3; j ++){
-        entry[i][j] = 0;
-        txt[i][j]->setText("0");
-      }
-    }
-    colorMap->data()->clear();
-    UpdatePlot();
-  }
-
-  void Fill(double x, double y){
-    if( isBusy ) return;
-    int xIndex, yIndex;
-    colorMap->data()->coordToCell(x, y, &xIndex, &yIndex);
-    //printf("%f,  %d  %d| %f, %d %d\n", x, xIndex, xBin, y, yIndex, yBin);
-
-    int xk = 1, yk = 1;
-    if( xIndex < 0 ) xk = 0;
-    if( xIndex >= xBin ) xk = 2;
-    if( yIndex < 0 ) yk = 0;
-    if( yIndex >= yBin ) yk = 2;
-    entry[xk][yk] ++;
-
-    txt[xk][yk]->setText(QString::number(entry[xk][yk]));
-
-    if( xk == 1 && yk == 1 ) {
-      double value = colorMap->data()->cell(xIndex, yIndex);
-      colorMap->data()->setCell(xIndex, yIndex, value + 1);
-
-      for( int i = 0; i < cutList.count(); i++){
-        if( cutList[i].isEmpty() ) continue;
-        if( cutList[i].containsPoint(QPointF(x,y), Qt::OddEvenFill) ) cutEntryList[i] ++;
-      }
-    }
-  }
-
-  void DrawCut(){
-
-    //The histogram is the 1st plottable.
-    // the lastPlottableID should be numCut+ 1
-    if( lastPlottableID != numCut ){
-      removePlottable(lastPlottableID);
-    }
-    
-    if(tempCut.size() > 0) {
-        QCPCurve *polygon = new QCPCurve(xAxis, yAxis);
-        lastPlottableID = plottableCount() - 1;
-
-        int colorID = tempCutID% colorCycle.count();
-        QPen pen(colorCycle[colorID].first);
-        pen.setWidth(1);
-        polygon->setPen(pen);
-
-        QVector<QCPCurveData> dataPoints;
-        for (const QPointF& point : tempCut) {
-            dataPoints.append(QCPCurveData(dataPoints.size(), point.x(), point.y()));
-        }
-        polygon->data()->set(dataPoints, false);
-    }
-    replot();
-
-    //qDebug() << "Plottable count : " <<  plottableCount() << ", cutList.count :" << cutList.count() << ", cutID :" << lastPlottableID;
-  }
-
-  void ClearAllCuts(){
-    numCut = 0;
-    tempCutID = -1;
-    lastPlottableID = -1;
-    cutList.clear();
-    cutIDList.clear();
-    for( int i = cutTextIDList.count() - 1; i >= 0 ; i--){
-      if( cutTextIDList[i] < 0 ) continue;
-      removeItem(cutTextIDList[i]);
-      removePlottable(plottableIDList[i]);
-    }
-    replot();
-
-    cutTextIDList.clear();
-    plottableIDList.clear();
-    cutNameList.clear();
-    cutEntryList.clear();
-  }
+  void DrawCut();
+  void ClearAllCuts();
 
   QList<QPolygonF> GetCutList() const{return cutList;} // this list may contain empty element
   QList<int> GetCutEntryList() const{ return cutEntryList;}
-  void PrintCutEntry() const{
-    if( numCut == 0 ) return;
-    printf("=============== There are %d cuts.\n", numCut);
-    for( int i = 0; i < cutList.count(); i++){
-      if( cutList[i].isEmpty() ) continue;
-      printf("%10s | %d \n", cutNameList[i].toStdString().c_str(), cutEntryList[i]);  
-    }
-  }
+  QList<QString> GetCutNameList() const { return cutNameList;}
+  void PrintCutEntry() const;
 
 private:
   double xMin, xMax, yMin, yMax;
@@ -470,104 +226,367 @@ private:
 
   bool isBusy;
 
-  //^======================== Right Mouse click action
-  void rightMouseClickRebin(){
-    QDialog dialog(this);
-    dialog.setWindowTitle("Rebin histogram");
-
-    QFormLayout layout(&dialog);
-
-    QLabel * info = new QLabel(&dialog);
-    info->setStyleSheet("color:red;");
-    info->setText("This will also clear histogram!!");
-    layout.addRow(info);
-
-    QStringList nameListX = {"Num. x-Bin", "x-Min", "x-Max"};
-    QLineEdit* lineEditX[3];
-    for (int i = 0; i < 3; ++i) {
-        lineEditX[i] = new QLineEdit(&dialog);
-        layout.addRow(nameListX[i] + " : ", lineEditX[i]);
-    }
-    lineEditX[0]->setText(QString::number(xBin));
-    lineEditX[1]->setText(QString::number(xMin));
-    lineEditX[2]->setText(QString::number(xMax));
-
-    QStringList nameListY = {"Num. y-Bin", "y-Min", "y-Max"};
-    QLineEdit* lineEditY[3];
-    for (int i = 0; i < 3; ++i) {
-        lineEditY[i] = new QLineEdit(&dialog);
-        layout.addRow(nameListY[i] + " : ", lineEditY[i]);
-    }
-    lineEditY[0]->setText(QString::number(yBin));
-    lineEditY[1]->setText(QString::number(yMin));
-    lineEditY[2]->setText(QString::number(yMax));
-
-    QLabel * msg = new QLabel(&dialog);
-    msg->setStyleSheet("color:red;");
-    layout.addRow(msg);
-
-    QDialogButtonBox buttonBox(QDialogButtonBox::Ok | QDialogButtonBox::Cancel, Qt::Horizontal, &dialog);
-    layout.addRow(&buttonBox);
-
-    double number[3][2];
-
-    QObject::connect(&buttonBox, &QDialogButtonBox::accepted, [&]() {
-        int OKcount = 0;
-        bool conversionOk = true;
-        for( int i = 0; i < 3; i++ ){
-          number[i][0] = lineEditX[i]->text().toDouble(&conversionOk);
-          if( conversionOk ){
-            OKcount++;
-          }else{
-            msg->setText(nameListX[i] + " is invalid.");
-            return;
-          }
-        }
-        for( int i = 0; i < 3; i++ ){
-          number[i][1] = lineEditY[i]->text().toDouble(&conversionOk);
-          if( conversionOk ){
-            OKcount++;
-          }else{
-            msg->setText(nameListY[i] + " is invalid.");
-            return;
-          }
-        }
-
-        if( OKcount == 6 ) {
-          if( number[0][0] <= 0 ) {
-            msg->setText( nameListX[0] + " is zero or negative" );
-            return;
-          }
-          if( number[0][0] <= 0 ) {
-            msg->setText( nameListX[0] + " is zero or negative" );
-            return;
-          }
-
-          if( number[2][0] > number[1][0] && number[2][1] > number[1][1]  ) {
-            dialog.accept();
-          }else{
-            if( number[2][0] > number[1][0] ){
-              msg->setText(nameListX[2] + " is smaller than " + nameListX[1]);
-            }
-            if( number[2][1] > number[1][1] ){
-              msg->setText(nameListY[2] + " is smaller than " + nameListY[1]);
-            }
-          }
-        }
-    });
-
-    QObject::connect(&buttonBox, &QDialogButtonBox::rejected, [&]() { dialog.reject();});
-
-    if( dialog.exec() == QDialog::Accepted ){
-      isBusy = true;
-      Rebin((int)number[0][0], number[1][0], number[2][0], (int)number[0][1], number[1][1], number[2][1]);
-      rescaleAxes();
-      UpdatePlot();
-      isBusy = false;
-    }
-
-  }
+  void rightMouseClickMenu(QMouseEvent * event);
+  void rightMouseClickRebin();
 
 };
 
+//^###############################################
+//^###############################################
+
+inline void Histogram2D::Fill(double x, double y){
+  if( isBusy ) return;
+  int xIndex, yIndex;
+  colorMap->data()->coordToCell(x, y, &xIndex, &yIndex);
+  //printf("%f,  %d  %d| %f, %d %d\n", x, xIndex, xBin, y, yIndex, yBin);
+
+  int xk = 1, yk = 1;
+  if( xIndex < 0 ) xk = 0;
+  if( xIndex >= xBin ) xk = 2;
+  if( yIndex < 0 ) yk = 0;
+  if( yIndex >= yBin ) yk = 2;
+  entry[xk][yk] ++;
+
+  txt[xk][yk]->setText(QString::number(entry[xk][yk]));
+
+  if( xk == 1 && yk == 1 ) {
+    double value = colorMap->data()->cell(xIndex, yIndex);
+    colorMap->data()->setCell(xIndex, yIndex, value + 1);
+
+    for( int i = 0; i < cutList.count(); i++){
+      if( cutList[i].isEmpty() ) continue;
+      if( cutList[i].containsPoint(QPointF(x,y), Qt::OddEvenFill) ) cutEntryList[i] ++;
+    }
+  }
+}
+
+inline  void Histogram2D::Rebin(int xbin, double xmin, double xmax, int ybin, double ymin, double ymax){
+  xMin = xmin;
+  xMax = xmax;
+  yMin = ymin;
+  yMax = ymax;
+  xBin = xbin;
+  yBin = ybin;
+
+  colorMap->data()->clear();
+  colorMap->data()->setSize(xBin, yBin);
+  colorMap->data()->setRange(QCPRange(xMin, xMax), QCPRange(yMin, yMax));
+
+  for( int i = 0; i < 3; i ++){
+    for( int j = 0; j < 3; j ++){
+      entry[i][j] = 0;
+      if( txt[i][j] ) txt[i][j]->setText("0");
+    }
+  }
+
+}
+
+inline void Histogram2D::Clear(){
+  for( int i = 0; i < 3; i ++){
+    for( int j = 0; j < 3; j ++){
+      entry[i][j] = 0;
+      txt[i][j]->setText("0");
+    }
+  }
+  colorMap->data()->clear();
+  colorMap->data()->setSize(xBin, yBin);
+  colorMap->data()->setRange(QCPRange(xMin, xMax), QCPRange(yMin, yMax));
+
+  UpdatePlot();
+}
+
+
+inline void Histogram2D::ClearAllCuts(){
+  numCut = 0;
+  tempCutID = -1;
+  lastPlottableID = -1;
+  cutList.clear();
+  cutIDList.clear();
+  for( int i = cutTextIDList.count() - 1; i >= 0 ; i--){
+    if( cutTextIDList[i] < 0 ) continue;
+    removeItem(cutTextIDList[i]);
+    removePlottable(plottableIDList[i]);
+  }
+  replot();
+
+  cutTextIDList.clear();
+  plottableIDList.clear();
+  cutNameList.clear();
+  cutEntryList.clear();
+}
+
+inline void Histogram2D::PrintCutEntry() const{
+  if( numCut == 0 ) return;
+  printf("=============== There are %d cuts.\n", numCut);
+  for( int i = 0; i < cutList.count(); i++){
+    if( cutList[i].isEmpty() ) continue;
+    printf("%10s | %d \n", cutNameList[i].toStdString().c_str(), cutEntryList[i]);  
+  }
+}
+
+inline void Histogram2D::DrawCut(){
+
+  //The histogram is the 1st plottable.
+  // the lastPlottableID should be numCut+ 1
+  if( lastPlottableID != numCut ){
+    removePlottable(lastPlottableID);
+  }
+  
+  if(tempCut.size() > 0) {
+      QCPCurve *polygon = new QCPCurve(xAxis, yAxis);
+      lastPlottableID = plottableCount() - 1;
+
+      int colorID = tempCutID% colorCycle.count();
+      QPen pen(colorCycle[colorID].first);
+      pen.setWidth(1);
+      polygon->setPen(pen);
+
+      QVector<QCPCurveData> dataPoints;
+      for (const QPointF& point : tempCut) {
+          dataPoints.append(QCPCurveData(dataPoints.size(), point.x(), point.y()));
+      }
+      polygon->data()->set(dataPoints, false);
+  }
+  replot();
+
+  //qDebug() << "Plottable count : " <<  plottableCount() << ", cutList.count :" << cutList.count() << ", cutID :" << lastPlottableID;
+}
+
+inline void Histogram2D::rightMouseClickMenu(QMouseEvent * event){
+  usingMenu = true;
+  setSelectionRectMode(QCP::SelectionRectMode::srmNone);
+
+  QMenu *menu = new QMenu(this);
+  menu->setAttribute(Qt::WA_DeleteOnClose);
+
+  QAction * a1 = menu->addAction("UnZoom");
+  QAction * a2 = menu->addAction("Clear hist.");
+  QAction * a3 = menu->addAction("Toggle Stat.");
+  QAction * a4 = menu->addAction("Rebin (clear histogram)");
+  QAction * a5 = menu->addAction("Create a Cut");
+  if( numCut > 0 ) {
+    menu->addSeparator();
+    menu->addAction("Add/Edit names to Cuts");
+    menu->addAction("Clear all Cuts");
+  }
+  for( int i = 0; i < cutList.size(); i++){
+    if( cutList[i].isEmpty()) continue;
+    QString haha = "";
+    menu->addAction("Delete " + cutNameList[i] + " ["+ colorCycle[cutIDList[i]%colorCycle.count()].second+"]");
+  }
+
+  QAction *selectedAction = menu->exec(event->globalPosition().toPoint());
+
+  if( selectedAction == a1 ){
+    xAxis->setRangeLower(xMin);
+    xAxis->setRangeUpper(xMax);
+    yAxis->setRangeLower(yMin);
+    yAxis->setRangeUpper(yMax);
+    replot();
+    usingMenu = false;
+    return;
+  }
+
+  if( selectedAction == a2 ) {
+    Clear();
+    usingMenu = false;
+    return;
+  }
+
+  if( selectedAction == a3 ){
+    for( int i = 0; i < 3; i ++ ){
+      for( int j = 0; j < 3; j ++ ){
+        box[i][j]->setVisible( !box[i][j]->visible());
+        txt[i][j]->setVisible( !txt[i][j]->visible());
+      }
+    }
+    replot();
+    usingMenu = false;
+    return;
+  }
+
+  if( selectedAction == a4){
+    rightMouseClickRebin();
+    usingMenu = false;
+    return;
+  }
+
+  if( selectedAction == a5 ){
+    tempCut.clear();
+    tempCutID ++;
+    isDrawCut= true;
+    usingMenu = false;
+    numCut ++;
+    return;
+  }
+
+  if( selectedAction && numCut > 0 && selectedAction->text().contains("Delete ") ){
+
+    QString haha = selectedAction->text();
+    int index1 = haha.indexOf("-");
+    int index2 = haha.indexOf("[");
+    int cutID = haha.mid(index1+1, index2-index1-1).remove(' ').toInt();
+    
+    removeItem(cutTextIDList[cutID]);
+    removePlottable(plottableIDList[cutID]);
+    replot();
+
+    numCut --;
+    cutList[cutID].clear();
+    cutIDList[cutID] = -1;
+    cutTextIDList[cutID] = -1;
+    plottableIDList[cutID] = -1;
+    cutNameList[cutID] = "";
+    cutEntryList[cutID] = -1;
+
+    for( int i = cutID + 1; i < cutTextIDList.count() ; i++){
+        cutTextIDList[i] --;
+        plottableIDList[i] --;
+    }
+
+    if( numCut == 0 ){
+      tempCutID = -1;
+      lastPlottableID = -1;
+      cutList.clear();
+      cutIDList.clear();
+      cutTextIDList.clear();
+      plottableIDList.clear();
+      cutNameList.clear();
+      cutEntryList.clear();
+    }
+    return;
+  }
+
+  if( selectedAction && numCut > 0 && selectedAction->text().contains("Clear all Cuts") ){
+    ClearAllCuts();
+    return;
+  }
+
+  if( selectedAction && numCut > 0 && selectedAction->text().contains("Add/Edit names to Cuts") ){
+    
+    QDialog dialog(this);
+    dialog.setWindowTitle("Add/Edit name of cuts ");
+
+    QFormLayout layout(&dialog);
+
+    for(int i = 0; i < cutTextIDList.count(); i++){
+      if( cutTextIDList[i] < 0 ) continue;
+      QLineEdit * le = new QLineEdit(&dialog);
+      layout.addRow(colorCycle[i%colorCycle.count()].second, le);
+      le->setText( cutNameList[i] );
+      connect(le, &QLineEdit::textChanged, this, [=](){
+        le->setStyleSheet("color : blue;");
+      });
+      connect(le, &QLineEdit::returnPressed, this, [=](){
+        le->setStyleSheet("");
+        cutNameList[i] = le->text();
+        ((QCPItemText *) this->item(cutTextIDList[i]))->setText(le->text());
+        replot();
+      });
+    }
+    dialog.exec();
+    return;
+  }
+
+
+}
+
+inline void Histogram2D::rightMouseClickRebin(){
+  QDialog dialog(this);
+  dialog.setWindowTitle("Rebin histogram");
+
+  QFormLayout layout(&dialog);
+
+  QLabel * info = new QLabel(&dialog);
+  info->setStyleSheet("color:red;");
+  info->setText("This will also clear histogram!!");
+  layout.addRow(info);
+
+  QStringList nameListX = {"Num. x-Bin", "x-Min", "x-Max"};
+  QLineEdit* lineEditX[3];
+  for (int i = 0; i < 3; ++i) {
+      lineEditX[i] = new QLineEdit(&dialog);
+      layout.addRow(nameListX[i] + " : ", lineEditX[i]);
+  }
+  lineEditX[0]->setText(QString::number(xBin));
+  lineEditX[1]->setText(QString::number(xMin));
+  lineEditX[2]->setText(QString::number(xMax));
+
+  QStringList nameListY = {"Num. y-Bin", "y-Min", "y-Max"};
+  QLineEdit* lineEditY[3];
+  for (int i = 0; i < 3; ++i) {
+      lineEditY[i] = new QLineEdit(&dialog);
+      layout.addRow(nameListY[i] + " : ", lineEditY[i]);
+  }
+  lineEditY[0]->setText(QString::number(yBin));
+  lineEditY[1]->setText(QString::number(yMin));
+  lineEditY[2]->setText(QString::number(yMax));
+
+  QLabel * msg = new QLabel(&dialog);
+  msg->setStyleSheet("color:red;");
+  layout.addRow(msg);
+
+  QDialogButtonBox buttonBox(QDialogButtonBox::Ok | QDialogButtonBox::Cancel, Qt::Horizontal, &dialog);
+  layout.addRow(&buttonBox);
+
+  double number[3][2];
+
+  QObject::connect(&buttonBox, &QDialogButtonBox::accepted, [&]() {
+      int OKcount = 0;
+      bool conversionOk = true;
+      for( int i = 0; i < 3; i++ ){
+        number[i][0] = lineEditX[i]->text().toDouble(&conversionOk);
+        if( conversionOk ){
+          OKcount++;
+        }else{
+          msg->setText(nameListX[i] + " is invalid.");
+          return;
+        }
+      }
+      for( int i = 0; i < 3; i++ ){
+        number[i][1] = lineEditY[i]->text().toDouble(&conversionOk);
+        if( conversionOk ){
+          OKcount++;
+        }else{
+          msg->setText(nameListY[i] + " is invalid.");
+          return;
+        }
+      }
+
+      if( OKcount == 6 ) {
+        if( number[0][0] <= 0 ) {
+          msg->setText( nameListX[0] + " is zero or negative" );
+          return;
+        }
+        if( number[0][0] <= 0 ) {
+          msg->setText( nameListX[0] + " is zero or negative" );
+          return;
+        }
+
+        if( number[2][0] > number[1][0] && number[2][1] > number[1][1]  ) {
+          dialog.accept();
+        }else{
+          if( number[2][0] > number[1][0] ){
+            msg->setText(nameListX[2] + " is smaller than " + nameListX[1]);
+          }
+          if( number[2][1] > number[1][1] ){
+            msg->setText(nameListY[2] + " is smaller than " + nameListY[1]);
+          }
+        }
+      }
+  });
+
+  QObject::connect(&buttonBox, &QDialogButtonBox::rejected, [&]() { dialog.reject();});
+
+  if( dialog.exec() == QDialog::Accepted ){
+    isBusy = true;
+    Rebin((int)number[0][0], number[1][0], number[2][0], (int)number[0][1], number[1][1], number[2][1]);
+    rescaleAxes();
+    UpdatePlot();
+    isBusy = false;
+  }
+
+}
+
+
 #endif
\ No newline at end of file
diff --git a/MultiBuilder.cpp b/MultiBuilder.cpp
index 69eede3..f15e62c 100644
--- a/MultiBuilder.cpp
+++ b/MultiBuilder.cpp
@@ -92,6 +92,7 @@ void MultiBuilder::ClearEvents(){
 
     nExhaushedCh = 0;
   }
+
 }
 
 void MultiBuilder::PrintStat(){
@@ -292,7 +293,7 @@ void MultiBuilder::BuildEvents(bool isFinal, bool skipTrace, bool verbose){
 
 }
 
-void MultiBuilder::BuildEventsBackWard(bool verbose){
+void MultiBuilder::BuildEventsBackWard(int maxNumEvent, bool verbose){
 
   //skip trace, and only build for 100 events max
 
@@ -375,7 +376,7 @@ void MultiBuilder::BuildEventsBackWard(bool verbose){
 
     }
 
-  }while(nExhaushedCh < nData * MaxNChannels && eventBuilt < 100);
+  }while(nExhaushedCh < nData * MaxNChannels && eventBuilt <= maxNumEvent);
 
   // // remember the end of DataIndex, prevent over build
   // for( int k = 0; k < nData; k++){
diff --git a/MultiBuilder.h b/MultiBuilder.h
index 542dba7..ae2fa44 100644
--- a/MultiBuilder.h
+++ b/MultiBuilder.h
@@ -32,10 +32,13 @@ public:
     fineTime = 0;
     trace.clear();
   }
+
+  void Print(){
+    printf("(%2d, %2d)[%3d] %6d %10llu, %5ld\n", bd, ch, sn, energy, timestamp, trace.size());
+  }
+
 };
 
-
-
 class MultiBuilder {
 
 public:
@@ -56,7 +59,7 @@ public:
   std::vector<int> GetDigiIDList() const {return idList;}
 
   void BuildEvents(bool isFinal = false, bool skipTrace = false, bool verbose = false);
-  void BuildEventsBackWard(bool verbose = false); // always skip trace, for faster online building 
+  void BuildEventsBackWard(int maxNumEvent = 100, bool verbose = false); // always skip trace, for faster online building 
 
   void ClearEvents();
   void PrintStat();
diff --git a/RegisterAddress.h b/RegisterAddress.h
index a43bedc..bb83175 100644
--- a/RegisterAddress.h
+++ b/RegisterAddress.h
@@ -63,7 +63,7 @@ class Reg{
     RW           GetType()         const {return type;}
     bool         IsCoupled()       const {return group;}
     unsigned int GetMaxBit()       const {return maxBit;} 
-    int          GetPartialStep()  const {return partialStep;} /// step = partialStep * ch2ns, -1 : step = 1
+    int          GetPartialStep()  const {return partialStep;} /// step = partialStep * tick2ns, -1 : step = 1
     void         Print()           const ;
 
     std::vector<std::pair<std::string, unsigned int>> GetComboList() const {return comboList;}
diff --git a/Scope.cpp b/Scope.cpp
index 37ff8a1..5f163e0 100644
--- a/Scope.cpp
+++ b/Scope.cpp
@@ -101,12 +101,12 @@ Scope::Scope(Digitizer ** digi, unsigned int nDigi, ReadDataThread ** readDataTh
   ID = 0;
   cbScopeDigi->setCurrentIndex(0);
   for( int i = 0; i < digi[0]->GetNChannels(); i++) cbScopeCh->addItem("Ch-" + QString::number(i));
-  ch2ns = digi[ID]->GetCh2ns();
+  tick2ns = digi[ID]->GetTick2ns();
 
   connect(cbScopeDigi, &RComboBox::currentIndexChanged, this, [=](int index){
     if( !enableSignalSlot ) return;
     ID = index;
-    ch2ns = digi[ID]->GetCh2ns();
+    tick2ns = digi[ID]->GetTick2ns();
     //---setup cbScopeCh
     cbScopeCh->clear();
     for( int i = 0; i < digi[ID]->GetNChannels(); i++) cbScopeCh->addItem("Ch-" + QString::number(i));
@@ -310,7 +310,7 @@ void Scope::UpdateScope(){
 
   if( digi[ID]->GetChannelOnOff(ch) == false) return;
 
-  int ch2ns = digi[ID]->GetCh2ns();
+  int tick2ns = digi[ID]->GetTick2ns();
   int factor = digi[ID]->IsDualTrace_PHA() ? 2 : 1;
 
   digiMTX[ID].lock();
@@ -329,19 +329,19 @@ void Scope::UpdateScope(){
     QVector<QPointF> points[4];
     if( digi[ID]->GetDPPType() == V1730_DPP_PHA_CODE ) {
       for( int i = 0; i < (int) (data->Waveform1[ch][index]).size() ; i++ ) {
-        points[0].append(QPointF(ch2ns * i * factor, (data->Waveform1[ch][index])[i])); 
-        if( i < (int) data->Waveform2[ch][index].size() )  points[1].append(QPointF(ch2ns * i * factor, (data->Waveform2[ch][index])[i]));
-        if( i < (int) data->DigiWaveform1[ch][index].size() )  points[2].append(QPointF(ch2ns * i * factor, (data->DigiWaveform1[ch][index])[i] * 1000));
-        if( i < (int) data->DigiWaveform2[ch][index].size() )  points[3].append(QPointF(ch2ns * i * factor, (data->DigiWaveform2[ch][index])[i] * 1000 + 500));
+        points[0].append(QPointF(tick2ns * i * factor, (data->Waveform1[ch][index])[i])); 
+        if( i < (int) data->Waveform2[ch][index].size() )  points[1].append(QPointF(tick2ns * i * factor, (data->Waveform2[ch][index])[i]));
+        if( i < (int) data->DigiWaveform1[ch][index].size() )  points[2].append(QPointF(tick2ns * i * factor, (data->DigiWaveform1[ch][index])[i] * 1000));
+        if( i < (int) data->DigiWaveform2[ch][index].size() )  points[3].append(QPointF(tick2ns * i * factor, (data->DigiWaveform2[ch][index])[i] * 1000 + 500));
       }
     }
 
     if( digi[ID]->GetDPPType() == V1730_DPP_PSD_CODE ) {
       for( int i = 0; i < (int) (data->DigiWaveform1[ch][index]).size() ; i++ ) {
-        points[0].append(QPointF(ch2ns * i * factor, (data->Waveform1[ch][index])[i])); 
-        if( i < (int) data->Waveform2[ch][index].size() )  points[1].append(QPointF(ch2ns * i * factor, (data->Waveform2[ch][index])[i]));
-        if( i < (int) data->DigiWaveform1[ch][index].size() )  points[2].append(QPointF(ch2ns * i, (data->DigiWaveform1[ch][index])[i] * 1000));
-        if( i < (int) data->DigiWaveform2[ch][index].size() )  points[3].append(QPointF(ch2ns * i, (data->DigiWaveform2[ch][index])[i] * 1000 + 500));
+        points[0].append(QPointF(tick2ns * i * factor, (data->Waveform1[ch][index])[i])); 
+        if( i < (int) data->Waveform2[ch][index].size() )  points[1].append(QPointF(tick2ns * i * factor, (data->Waveform2[ch][index])[i]));
+        if( i < (int) data->DigiWaveform1[ch][index].size() )  points[2].append(QPointF(tick2ns * i, (data->DigiWaveform1[ch][index])[i] * 1000));
+        if( i < (int) data->DigiWaveform2[ch][index].size() )  points[3].append(QPointF(tick2ns * i, (data->DigiWaveform2[ch][index])[i] * 1000 + 500));
       }
     }
     dataTrace[0]->replace(points[0]);
@@ -351,7 +351,7 @@ void Scope::UpdateScope(){
   }
   digiMTX[ID].unlock();
 
-  plot->axes(Qt::Horizontal).first()->setRange(0, ch2ns * traceLength * factor);
+  plot->axes(Qt::Horizontal).first()->setRange(0, tick2ns * traceLength * factor);
 
   emit UpdateScaler();
 
@@ -412,8 +412,8 @@ void Scope::SetUpSpinBox(RSpinBox * &sb, QString str, int row, int col, const Re
   sb = new RSpinBox(settingGroup);
   if( para.GetPartialStep() != 0 ){
     sb->setMinimum(0);
-    sb->setMaximum(para.GetMaxBit() * para.GetPartialStep() * ch2ns);
-    if( para.GetPartialStep() > 0 ) sb->setSingleStep(para.GetPartialStep() * ch2ns);
+    sb->setMaximum(para.GetMaxBit() * para.GetPartialStep() * tick2ns);
+    if( para.GetPartialStep() > 0 ) sb->setSingleStep(para.GetPartialStep() * tick2ns);
     if( para.GetPartialStep() == -1 ) sb->setSingleStep(1);
   }
   settingLayout->addWidget(sb, row, col + 1);
@@ -438,7 +438,7 @@ void Scope::SetUpSpinBox(RSpinBox * &sb, QString str, int row, int col, const Re
     msg = QString::fromStdString(para.GetName()) + "|DIG:"+ QString::number(digi[ID]->GetSerialNumber()) + ",CH:" + (ch == -1 ? "All" : QString::number(ch));
     msg += " = " + QString::number(sb->value());
 
-    uint32_t value = sb->value() / ch2ns / abs(para.GetPartialStep());
+    uint32_t value = sb->value() / tick2ns / abs(para.GetPartialStep());
 
     if( para == DPP::RecordLength_G){
       int factor = digi[ID]->IsDualTrace_PHA() ? 2 : 1;
@@ -694,7 +694,7 @@ void Scope::UpdateSpinBox(RSpinBox * &sb, const Reg para){
   enableSignalSlot = false;
   unsigned int haha = digi[ID]->GetSettingFromMemory(para, ch);
 
-  if( para.GetPartialStep() >   0 ) sb->setValue(haha * para.GetPartialStep() * ch2ns);
+  if( para.GetPartialStep() >   0 ) sb->setValue(haha * para.GetPartialStep() * tick2ns);
   if( para.GetPartialStep() == -1 ) sb->setValue(haha);
   //enableSignalSlot = true;
 }
@@ -708,11 +708,11 @@ void Scope::UpdatePanelFromMomeory(){
   int ch = cbScopeCh->currentIndex();
 
   unsigned int haha = digi[ID]->GetSettingFromMemory(DPP::RecordLength_G, ch);
-  sbReordLength->setValue(haha * DPP::RecordLength_G.GetPartialStep() * ch2ns);
+  sbReordLength->setValue(haha * DPP::RecordLength_G.GetPartialStep() * tick2ns);
 
   // if( digi[ID]->GetDPPType() == V1730_DPP_PHA_CODE ){
   //   int factor = digi[ID]->IsDualTrace() ? 2 : 1; // if dual trace, 
-  //   sbReordLength->setValue(haha * DPP::RecordLength_G.GetPartialStep() * ch2ns / factor);
+  //   sbReordLength->setValue(haha * DPP::RecordLength_G.GetPartialStep() * tick2ns / factor);
   // }else{
   // }
 
diff --git a/Scope.h b/Scope.h
index 013fee9..b482ee2 100644
--- a/Scope.h
+++ b/Scope.h
@@ -71,7 +71,7 @@ private:
   Digitizer ** digi;
   unsigned short nDigi;
   unsigned short ID; // the id of digi, index of cbScopeDigi
-  int ch2ns;
+  int tick2ns;
   bool traceOn[MaxNDigitizer];
 
   ReadDataThread ** readDataThread;   
diff --git a/SplitPoleAnalyzer.h b/SplitPoleAnalyzer.h
index 29dec70..1b39075 100644
--- a/SplitPoleAnalyzer.h
+++ b/SplitPoleAnalyzer.h
@@ -26,9 +26,15 @@ public:
 
     SetUpdateTimeInSec(1.0);
 
-    RedefineEventBuilder({0}); // only build for the 0-th digitizer;
+    RedefineEventBuilder({0}); // only build for the 0-th digitizer, otherwise, it will build event accross all digitizers
+    tick2ns = digi[0]->GetTick2ns();
+    SetBackwardBuild(false, 500); // using normal building (acceding in time) or backward building, int the case of backward building, default events to be build is 100. 
     evtbder = GetEventBuilder();
 
+    //========== use the influx from the Analyzer
+    influx = new InfluxDB("https://fsunuc.physics.fsu.edu/influx/");
+    dataBaseName = "testing"; 
+
     SetUpCanvas();
   }
 
@@ -47,6 +53,8 @@ private:
   Histogram2D * h2;
   Histogram1D * h1;
 
+  int tick2ns;
+
 };
 
 
@@ -55,12 +63,13 @@ inline void SplitPole::SetUpCanvas(){
   setGeometry(0, 0, 1600, 800);  
 
   // the "this" make the histogram a child of the SplitPole class. When SplitPole destory, all childs destory as well.
-  h2 = new Histogram2D("Split Pole PID", "x", "y", 400, 0, 10000, 400, 0, 10000, this);
+  h2 = new Histogram2D("Split Pole PID", "x", "y", 100, 0, 10000, 100, 0, 10000, this);
   //layout is inheriatge from Analyzer
   layout->addWidget(h2, 0, 0);
 
   h1 = new Histogram1D("Spectrum", "x", 400, 0, 10000, this);
   layout->addWidget(h1, 0, 1);
+  
 
 }
 
@@ -72,29 +81,61 @@ inline void SplitPole::UpdateHistograms(){
   long eventBuilt = evtbder->eventBuilt;
   if( eventBuilt == 0 ) return;
 
+  //============ Get the cut list, if any
+  QList<QPolygonF> cutList = h2->GetCutList();
+  const int nCut = cutList.count();
+  unsigned long long tMin[nCut] = {0xFFFFFFFFFFFFFFFF}, tMax[nCut] = {0};
+  unsigned int count[nCut]={0};
+
+  //============ Processing data and fill histograms
   long eventIndex = evtbder->eventIndex;
   long eventStart = eventIndex - eventBuilt + 1;
   if(eventStart < 0 ) eventStart += MaxNEvent;
-
-  //============ Processing data and fill histograms
-  unsigned short e1 = 0, e2 = 0;
-
+  
   for( long i = eventStart ; i <= eventIndex; i ++ ){
+    unsigned short e1 = 0, e2 = 0;
+    unsigned long long t1 = 0, t2 = 0;
     std::vector<EventMember> event = evtbder->events[i];
-
+    //printf("-------------- %ld\n", i);
     for( int k = 0; k < (int) event.size(); k++ ){
-      if( event[k].ch ==  9 ) e1 = event[k].energy;
-      if( event[k].ch == 10 ) e2 = event[k].energy;
+      //event[k].Print();
+      if( event[k].ch ==  9 ) {e1 = event[k].energy; t1 = event[k].timestamp;}
+      if( event[k].ch == 10 ) {e2 = event[k].energy; t2 = event[k].timestamp;}
     }
 
+    if( e1 == 0 ) continue;
+    if( e2 == 0 ) continue;
+
     h2->Fill(e1, e2);
     h1->Fill(e1);
+
+    //check events inside any Graphical cut and extract the rate, using t1 only
+    for(int p = 0; p < cutList.count(); p++ ){ 
+      if( cutList[p].isEmpty() ) continue;
+      if( cutList[p].containsPoint(QPointF(e1, e2), Qt::OddEvenFill) ){
+        if( t1 < tMin[p] ) tMin[p] = t1;
+        if( t1 > tMax[p] ) tMax[p] = t1;
+        count[p] ++;
+        //printf(".... %d \n", count[p]);
+      }
+    }
   }
 
   h2->UpdatePlot();
   h1->UpdatePlot();
 
-  h2->PrintCutEntry();
+  QList<QString> cutNameList = h2->GetCutNameList();
+  for( int p = 0; p < cutList.count(); p ++){
+    if( cutList[p].isEmpty() ) continue;
+    double dT = (tMax[p]-tMin[p]) * tick2ns / 1e9; // tick to sec
+    double rate = count[p]*1.0/(dT);
+    //printf("%llu %llu, %f %d\n", tMin[p], tMax[p], dT, count[p]);
+    //printf("%10s | %d | %f Hz \n", cutNameList[p].toStdString().c_str(), count[p], rate);  
+    
+    influx->AddDataPoint("Cut,name=" + cutNameList[p].toStdString()+ " value=" + std::to_string(rate));
+    influx->WriteData(dataBaseName);
+    influx->ClearDataPointsBuffer();
+  }
 
 }
 
diff --git a/test.cpp b/test.cpp
index 99adc7b..8196183 100644
--- a/test.cpp
+++ b/test.cpp
@@ -41,7 +41,7 @@ int main(int argc, char* argv[]){
   // dig[0]->ProgramBoard();
   // dig[0]->ProgramPSDBoard();
 
-  // const float ch2ns = dig[0]->GetCh2ns();
+  // const float tick2ns = dig[0]->GetTick2ns();
 
   Data * data =  dig[0]->GetData();
   data->ClearData();
@@ -117,7 +117,7 @@ int main(int argc, char* argv[]){
       
       unsigned short nData = data->DataIndex[0]; //channel-0
       haha = data->Waveform1[0][nData-1];
-      for( int i = 0; i < waveFormLength; i++) g1->SetPoint(i, i*ch2ns, haha[i]);
+      for( int i = 0; i < waveFormLength; i++) g1->SetPoint(i, i*tick2ns, haha[i]);
 
       canvas->cd(3); g1->Draw("AP");
       
diff --git a/test_indep.cpp b/test_indep.cpp
index 99f20dd..aabb612 100644
--- a/test_indep.cpp
+++ b/test_indep.cpp
@@ -13,7 +13,7 @@
 
 using namespace std;
 
-void PrintChannelSettingFromDigitizer(int handle, int ch, float ch2ns){
+void PrintChannelSettingFromDigitizer(int handle, int ch, float tick2ns){
   
   printf("\e[33m================================================\n");
   printf("================ Setting for channel %d \n", ch);
@@ -48,11 +48,11 @@ void PrintChannelSettingFromDigitizer(int handle, int ch, float ch2ns){
     default: extra2WordOptStr = "Reserved"; break;
   }
 
-  printf(" ch2ns : %.0f ns\n", ch2ns);
+  printf(" tick2ns : %.0f ns\n", tick2ns);
   
   printf("==========----- input \n");
-  CAEN_DGTZ_ReadRegister(handle, DPP::RecordLength_G + (ch << 8), value);    printf("%24s  %5d samples = %5.0f ns \n",   "Record Length",  ((value[0] * 8) & MaxRecordLength), ((value[0] * 8) & MaxRecordLength) * ch2ns); ///Record length
-  CAEN_DGTZ_ReadRegister(handle, DPP::PreTrigger + (ch << 8), value);        printf("%24s  %5d samples = %5.0f ns \n",   "Pre-tigger",  value[0] * 4, value[0] * 4 * ch2ns);    ///Pre-trigger
+  CAEN_DGTZ_ReadRegister(handle, DPP::RecordLength_G + (ch << 8), value);    printf("%24s  %5d samples = %5.0f ns \n",   "Record Length",  ((value[0] * 8) & MaxRecordLength), ((value[0] * 8) & MaxRecordLength) * tick2ns); ///Record length
+  CAEN_DGTZ_ReadRegister(handle, DPP::PreTrigger + (ch << 8), value);        printf("%24s  %5d samples = %5.0f ns \n",   "Pre-tigger",  value[0] * 4, value[0] * 4 * tick2ns);    ///Pre-trigger
                                                                                        printf("%24s  %5.0f samples, DPP-[20:22]\n", "baseline mean",  pow(4, 1 + baseline)); ///Ns baseline
   CAEN_DGTZ_ReadRegister(handle, DPP::ChannelDCOffset + (ch << 8), value);   printf("%24s  %.2f %% \n", "DC offset",  100.0 - value[0] * 100./ 0xFFFF); ///DC offset
   CAEN_DGTZ_ReadRegister(handle, DPP::InputDynamicRange + (ch << 8), value); printf("%24s  %.1f Vpp \n",     "input Dynamic",  value[0] == 0 ? 2 : 0.5); ///InputDynamic
@@ -60,27 +60,27 @@ void PrintChannelSettingFromDigitizer(int handle, int ch, float ch2ns){
 
   printf("==========----- discriminator \n");
   CAEN_DGTZ_ReadRegister(handle, DPP::PHA::TriggerThreshold + (ch << 8), value);     printf("%24s  %4d LSB\n",     "Threshold",  value[0]); ///Threshold
-  CAEN_DGTZ_ReadRegister(handle, DPP::PHA::TriggerHoldOffWidth + (ch << 8), value);  printf("%24s  %4d samples, %5.0f ns \n",   "trigger hold off", value[0],  value[0] * 4 * ch2ns); ///Trigger Hold off
-  CAEN_DGTZ_ReadRegister(handle, DPP::PHA::RCCR2SmoothingFactor + (ch << 8), value); printf("%24s  %4d samples, %5.0f ns \n", "Fast Dis. smoothing",  (value[0] & 0x1f) * 2, (value[0] & 0x1f) * 2 * ch2ns ); ///Fast Discriminator smoothing
-  CAEN_DGTZ_ReadRegister(handle, DPP::PHA::ShapedTriggerWidth + (ch << 8), value);   printf("%24s  %4d samples, %5.0f ns \n",   "Fast Dis. output width", value[0], value[0] * 4 * ch2ns); ///Fast Dis. output width
-  CAEN_DGTZ_ReadRegister(handle, DPP::PHA::InputRiseTime + (ch << 8), value);        printf("%24s  %4d samples, %5.0f ns \n",   "Input rise time ", value[0],  value[0] * 4 * ch2ns); ///Input rise time
+  CAEN_DGTZ_ReadRegister(handle, DPP::PHA::TriggerHoldOffWidth + (ch << 8), value);  printf("%24s  %4d samples, %5.0f ns \n",   "trigger hold off", value[0],  value[0] * 4 * tick2ns); ///Trigger Hold off
+  CAEN_DGTZ_ReadRegister(handle, DPP::PHA::RCCR2SmoothingFactor + (ch << 8), value); printf("%24s  %4d samples, %5.0f ns \n", "Fast Dis. smoothing",  (value[0] & 0x1f) * 2, (value[0] & 0x1f) * 2 * tick2ns ); ///Fast Discriminator smoothing
+  CAEN_DGTZ_ReadRegister(handle, DPP::PHA::ShapedTriggerWidth + (ch << 8), value);   printf("%24s  %4d samples, %5.0f ns \n",   "Fast Dis. output width", value[0], value[0] * 4 * tick2ns); ///Fast Dis. output width
+  CAEN_DGTZ_ReadRegister(handle, DPP::PHA::InputRiseTime + (ch << 8), value);        printf("%24s  %4d samples, %5.0f ns \n",   "Input rise time ", value[0],  value[0] * 4 * tick2ns); ///Input rise time
 
   printf("==========----- Trapezoid \n");
-  CAEN_DGTZ_ReadRegister(handle, DPP::PHA::TrapezoidRiseTime + (ch << 8), value); printf("%24s  %4d samples, %5.0f ns \n", "Trap. rise time", value[0], value[0] * 4 * ch2ns); ///Trap. rise time, 2 for 1 ch to 2ns
-  int riseTime = value[0] * 4 * ch2ns;
-  CAEN_DGTZ_ReadRegister(handle, DPP::PHA::TrapezoidFlatTop + (ch << 8), value);  printf("%24s  %4d samples, %5.0f ns \n", "Trap. flat time", value[0], value[0] * 4 * ch2ns); ///Trap. flat time
-  int flatTopTime = value[0] * 4 * ch2ns;
+  CAEN_DGTZ_ReadRegister(handle, DPP::PHA::TrapezoidRiseTime + (ch << 8), value); printf("%24s  %4d samples, %5.0f ns \n", "Trap. rise time", value[0], value[0] * 4 * tick2ns); ///Trap. rise time, 2 for 1 ch to 2ns
+  int riseTime = value[0] * 4 * tick2ns;
+  CAEN_DGTZ_ReadRegister(handle, DPP::PHA::TrapezoidFlatTop + (ch << 8), value);  printf("%24s  %4d samples, %5.0f ns \n", "Trap. flat time", value[0], value[0] * 4 * tick2ns); ///Trap. flat time
+  int flatTopTime = value[0] * 4 * tick2ns;
   double shift = log(riseTime * flatTopTime ) / log(2) - 2;
                                                                                             printf("%24s  %4d bit =? %.1f = Ceil( Log(rise [ns] x decay [ns])/Log(2) ), DPP-[0:5]\n", "Trap. Rescaling",  trapRescaling, shift ); ///Trap. Rescaling Factor
-  CAEN_DGTZ_ReadRegister(handle, DPP::PHA::DecayTime + (ch << 8), value);         printf("%24s  %4d samples, %5.0f ns \n",    "Decay time", value[0], value[0] * 4 * ch2ns); ///Trap. pole zero
-  CAEN_DGTZ_ReadRegister(handle, DPP::PHA::PeakingTime + (ch << 8), value);       printf("%24s  %4d samples, %5.0f ns = %.2f %% of FlatTop\n", "Peaking time",  value[0], value[0] * 4 * ch2ns, value[0] * 400. * ch2ns / flatTopTime ); ///Peaking time
-  CAEN_DGTZ_ReadRegister(handle, DPP::PHA::PeakHoldOff + (ch << 8), value);       printf("%24s  %4d samples, %5.0f ns \n",    "Peak hole off", value[0], value[0] * 4 *ch2ns ); ///Peak hold off
+  CAEN_DGTZ_ReadRegister(handle, DPP::PHA::DecayTime + (ch << 8), value);         printf("%24s  %4d samples, %5.0f ns \n",    "Decay time", value[0], value[0] * 4 * tick2ns); ///Trap. pole zero
+  CAEN_DGTZ_ReadRegister(handle, DPP::PHA::PeakingTime + (ch << 8), value);       printf("%24s  %4d samples, %5.0f ns = %.2f %% of FlatTop\n", "Peaking time",  value[0], value[0] * 4 * tick2ns, value[0] * 400. * tick2ns / flatTopTime ); ///Peaking time
+  CAEN_DGTZ_ReadRegister(handle, DPP::PHA::PeakHoldOff + (ch << 8), value);       printf("%24s  %4d samples, %5.0f ns \n",    "Peak hole off", value[0], value[0] * 4 *tick2ns ); ///Peak hold off
                                                                                             printf("%24s  %4.0f samples, DPP-[12:13]\n", "Peak mean",  pow(4, NsPeak)); ///Ns peak
 
   printf("==========----- Other \n");
   CAEN_DGTZ_ReadRegister(handle, DPP::PHA::FineGain + (ch << 8), value);                 printf("%24s  %d = 0x%x\n",  "Energy fine gain",  value[0], value[0]); ///Energy fine gain
   CAEN_DGTZ_ReadRegister(handle, DPP::ChannelADCTemperature_R + (ch << 8), value);         printf("%24s  %d C\n",     "Temperature",  value[0]); ///Temperature
-  CAEN_DGTZ_ReadRegister(handle, DPP::PHA::RiseTimeValidationWindow + (ch << 8), value); printf("%24s  %.0f ns \n", "RiseTime Vaild Win.",  value[0] * ch2ns); 
+  CAEN_DGTZ_ReadRegister(handle, DPP::PHA::RiseTimeValidationWindow + (ch << 8), value); printf("%24s  %.0f ns \n", "RiseTime Vaild Win.",  value[0] * tick2ns); 
   CAEN_DGTZ_ReadRegister(handle, DPP::PHA::ChannelStopAcquisition + (ch << 8), value);   printf("%24s  %d = %s \n", "Stop Acq bit", value[0] & 1 , (value[0] & 1 ) == 0 ? "Run" : "Stop"); 
   CAEN_DGTZ_ReadRegister(handle, DPP::ChannelStatus_R + (ch << 8), value);                 printf("%24s  0x%x \n",    "Status bit",  (value[0] & 0xff) ); 
   CAEN_DGTZ_ReadRegister(handle, DPP::AMCFirmwareRevision_R + (ch << 8), value);           printf("%24s  0x%x \n",    "AMC firmware rev.",  value[0] ); 
@@ -181,10 +181,10 @@ int main(int argc, char* argv[]){
   ret = (int) CAEN_DGTZ_GetInfo(handle, &BoardInfo);
   int NChannel = BoardInfo.Channels;
   uint32_t channelMask = 0xFFFF;
-  float ch2ns = 4.0;
+  float tick2ns = 4.0;
   switch(BoardInfo.Model){
-        case CAEN_DGTZ_V1730: ch2ns = 2.0; break; ///ns -> 500 MSamples/s
-        case CAEN_DGTZ_V1725: ch2ns = 4.0; break; ///ns -> 250 MSamples/s
+        case CAEN_DGTZ_V1730: tick2ns = 2.0; break; ///ns -> 500 MSamples/s
+        case CAEN_DGTZ_V1725: tick2ns = 4.0; break; ///ns -> 250 MSamples/s
   }
   unsigned int ADCbits = BoardInfo.ADC_NBits;
   
@@ -309,7 +309,7 @@ int main(int argc, char* argv[]){
   if( ret != 0 ) { printf("==== memory allocation error.\n"); return 0;}
   
   PrintBoardConfiguration(handle);
-  PrintChannelSettingFromDigitizer(handle, 4, ch2ns);
+  PrintChannelSettingFromDigitizer(handle, 4, tick2ns);
   
   printf("============ Start ACQ \n");
   CAEN_DGTZ_SWStartAcquisition(handle);