Work towards supporting spectra with y values less than one.

Initial solution towards issue #33 - still todo is to detect spectra with all very small counts, and automatically adjust y-range (current app logic expects roughly 1 count per channel as smallest non-zero y-values - roughly)

InterSpec/D3SpectrumDisplayDiv.h

@@ -189,6 +189,9 @@ class D3SpectrumDisplayDiv : public Wt::WContainerWidget
    */
   void setLogYAxisMin( const double ymin );
 
+  /** Returns the `m_logYAxisMin` value */
+  double logYAxisMin() const;
+
   // These 3 functions retrieve the corresponding info from the model.
   std::shared_ptr<const SpecUtils::Measurement> data()       const;
   std::shared_ptr<const SpecUtils::Measurement> secondData() const;

InterSpec/InterSpec.h

@@ -594,6 +594,9 @@ class InterSpec : public Wt::WContainerWidget
    (e.g., a negative lower counts was specified, but its currently log-scale)
    */
   bool setYAxisRange( float lower_counts, float upper_counts );
+
+  /** When displaying the spectrum in log-y, sets the lower y-axis value to show, if there are channels with zero counts. */
+  bool setLogYAxisMin( const double lower_value );
 
   //displayedSpectrumRange(): Grab the ranges in y and y that are currently
   //  displayed to the user.

InterSpec/TerminalModel.h

@@ -155,6 +155,7 @@ class TerminalModel {
       ClearVarCommand,
       SetEnergyRangeCommand,
       SetYaxisRangeCommand,
+      SetLogYAxisMinCommand,
       SearchPeakCommand,
       DeletePeakCommand,
       RefitPeakCommand,
@@ -175,6 +176,7 @@ class TerminalModel {
     std::string lighten       ( const std::string& arguments );
     std::string setEnergyRange( const std::string& arguments );
     std::string setYRange     ( const std::string& arguments );
+    std::string setLogYAxisMin( const std::string& arguments );
     std::string searchforPeak ( const std::string& arguments );
     std::string deletePeak    ( const std::string& arguments );
     std::string refitPeak     ( const std::string& arguments );

src/D3SpectrumDisplayDiv.cpp

@@ -1801,8 +1801,13 @@ void D3SpectrumDisplayDiv::setLogYAxisMin( const double ymin )
     doJavaScript( m_jsgraph + ".setLogYAxisMin(" + std::to_string(ymin) + ");" );
 
   scheduleUpdateForeground(); //JIC, the JS setPeakLabelRotation(...) wont cause a re-draw
-}//void setPeakLabelRotation( const double rotation )
+}//void setLogYAxisMin( const double ymin )
+
 
+double D3SpectrumDisplayDiv::logYAxisMin() const
+{
+  return m_logYAxisMin;
+}
 
 void D3SpectrumDisplayDiv::saveChartToImg( const std::string &filename, const bool asPng )
 {

src/InterSpec.cpp

@@ -12219,10 +12219,72 @@ bool InterSpec::setYAxisRange( float lower_counts, float upper_counts )
   if( upper_counts < lower_counts )
     std::swap( lower_counts, upper_counts );
 
-  if( (lower_counts <= 1.0E-6) && (upper_counts <= 1.0E-6) )
+  if( upper_counts == lower_counts )
     return false;
 
-  if( (lower_counts < 9.9E-7) && m_spectrum->yAxisIsLog() )
+  const bool isLogY = m_spectrum->yAxisIsLog();
+
+  // If user is setting suspiciously small values, lets do some sanity checks.
+  //  If log-y, there is a minimum lower y-value on the client side - we may need
+  //  to adjust this.
+  if( (isLogY &&
+       ((lower_counts < m_spectrum->logYAxisMin())
+        || (lower_counts < std::numeric_limits<float>::min())))
+     || (!isLogY && (lower_counts <= 1.0E-6) && (upper_counts <= 1.0E-6)) )
+  {
+    const auto hist = displayedHistogram(SpecUtils::SpectrumType::Foreground);
+    if( !hist || !hist->gamma_counts() || (hist->gamma_counts()->size() < 2) )
+      return false;
+
+    const shared_ptr<const vector<float>> &channels = hist->gamma_counts();
+
+    // Lets check the y-range - ignoring we may be showing multiple channels per display-bin,
+    // to see if the requested range is reasonable
+    double xmin, xmax, ymin, ymax;
+    m_spectrum->visibleRange( xmin, xmax, ymin, ymax );
+
+    const size_t lower_channel = hist->find_gamma_channel(xmin);
+    const size_t upper_channel = hist->find_gamma_channel(xmax);
+    float min_nonzero_value = std::numeric_limits<float>::max();
+    float max_value = -std::numeric_limits<float>::max();
+
+    for( size_t channel = lower_channel; channel <= upper_channel; ++channel )
+    {
+      if( channel < channels->size() )
+      {
+        const float val = (*channels)[channel];
+        max_value = std::max( max_value, val );
+        if( val > 0.0f )
+          min_nonzero_value = std::min( min_nonzero_value, val );
+      }//if( channel < channels->size() )
+    }//for( loop over visible channels )
+
+    if( upper_counts <= min_nonzero_value )
+      return false;
+
+    if( isLogY )
+    {
+      if( lower_counts <= 0.0f )
+      {
+        success = false;
+        lower_counts = 0.9 * min_nonzero_value;
+      }
+      if( upper_counts <= lower_counts )
+      {
+        success = false;
+        upper_counts = 10.0*lower_counts;
+      }
+
+      const double prevMinLogY = m_spectrum->logYAxisMin();
+      if( lower_counts < prevMinLogY )
+        m_spectrum->setLogYAxisMin( lower_counts );
+    }//if( isLogY )
+
+    m_spectrum->setYAxisRange( lower_counts, upper_counts );
+    return success;
+  }//
+
+  if( (lower_counts < 9.9E-7) && isLogY )
   {
     success = false;
     lower_counts = 1.0E-6;
@@ -12236,7 +12298,19 @@ bool InterSpec::setYAxisRange( float lower_counts, float upper_counts )
 }//bool setYAxisRange(...)
 
 
+bool InterSpec::setLogYAxisMin( const double lower_value )
+{
+  try
+  {
+    m_spectrum->setLogYAxisMin( lower_value );
+  }catch( std::exception & )
+  {
+    return false;
+  }
+  return true;
+}//setLogYAxisMin( float lower_value )
 
+
 void InterSpec::displayedSpectrumRange( double &xmin, double &xmax, double &ymin, double &ymax ) const
 {
   m_spectrum->visibleRange( xmin, xmax, ymin, ymax );

src/TerminalModel.cpp

@@ -631,6 +631,7 @@ TerminalModel::TerminalModel( InterSpec* viewer )
     addDropDownListHeader( "Spectrum Viewer Commands" );
     addCommand( "setRange"  , SetEnergyRangeCommand );
     addCommand( "setYRange"  , SetYaxisRangeCommand );
+    addCommand( "setLogYAxisMin"  , SetLogYAxisMinCommand );
     addDropDownListSeparator();
 
     addDropDownListHeader( "Nuclide Commands" );
@@ -1718,7 +1719,12 @@ void TerminalModel::addCommand(const std::string& command, CommandType type)
                            "Sets the displayed y-axis range of the current spectrum."
                            " Outputs if action was a success or not." );
     break;
-
+
+    case SetLogYAxisMinCommand:
+      addDropDownListItem( "setLogYAxisMin( lower_y_counts )",
+                          "y axis zooming counts range yrange axis zoom",
+                           "Sets the minimum displayed y-axis value when there is zero counts." );
+    break;
 
     default: break;
   }//switch( m_commandMap.at(command) )
@@ -1735,17 +1741,18 @@ std::string TerminalModel::doCommand(const std::string& input)
     const std::string& arguments = match[2];
 
     switch ( m_commandMap.at(command) ) {
-        case VarmapCommand:         return variableMapStr( arguments );
-        case SetEnergyRangeCommand: return setEnergyRange( arguments );
-        case SetYaxisRangeCommand:  return setYRange( arguments );
-        case SearchPeakCommand:     return searchforPeak ( arguments );
-        case DeletePeakCommand:     return deletePeak    ( arguments );
-        case RefitPeakCommand:      return refitPeak     ( arguments );
-        case DarkenCommand:         return darken        ( arguments );
-        case LightenCommand:        return lighten       ( arguments );
-        case SetNuclideCommand:     return setNuclide    ( arguments );
-        case SaveCommand:           return saveFile      ( arguments );
-        case ClearVarCommand:       return clearVar      ( arguments );
+        case VarmapCommand:          return variableMapStr( arguments );
+        case SetEnergyRangeCommand:  return setEnergyRange( arguments );
+        case SetYaxisRangeCommand:   return setYRange( arguments );
+        case SetLogYAxisMinCommand:  return setLogYAxisMin( arguments );
+        case SearchPeakCommand:      return searchforPeak ( arguments );
+        case DeletePeakCommand:      return deletePeak    ( arguments );
+        case RefitPeakCommand:       return refitPeak     ( arguments );
+        case DarkenCommand:          return darken        ( arguments );
+        case LightenCommand:         return lighten       ( arguments );
+        case SetNuclideCommand:      return setNuclide    ( arguments );
+        case SaveCommand:            return saveFile      ( arguments );
+        case ClearVarCommand:        return clearVar      ( arguments );
         default: break;
     }
     return "Error: unsupported command";
@@ -1902,9 +1909,10 @@ std::string TerminalModel::setYRange( const std::string& arguments )
     if (lower > upper)
       std::swap(lower, upper);
 
-    if( std::abs(upper - lower) <= 0.01 )
-      throw mup::ParserError( "Invalid arguments for function (setYRange). Lower and upper bound"
-                              " must not have difference less than or equal to 0.01." );
+    //const float diff = upper - lower;
+    //if( diff <= 0.0 )
+    //  throw mup::ParserError( "Invalid arguments for function (setYRange). Lower and upper bound"
+    //                           " must not have difference less than or equal to 0.01." );
 
     const bool success = m_viewer->setYAxisRange(lower, upper);
 
@@ -1923,6 +1931,30 @@ std::string TerminalModel::setYRange( const std::string& arguments )
 }//string TerminalModel::setYRange(string)
 
 
+std::string TerminalModel::setLogYAxisMin( const std::string& arguments )
+{
+  try 
+  {
+    m_parser->SetExpr( arguments );
+    const double counts = m_parser->Eval().GetFloat();
+
+    if( counts <= 0 )
+      throw std::runtime_error( "value must be larger than zero" );
+
+    if( !m_viewer->setLogYAxisMin(counts) )
+      return "Failed to set lower value.";
+  }catch( const mup::ParserError &e )
+  {
+    return errorMessage(e);
+  }catch( const std::exception &e )
+  {
+    return "Error: " + std::string(e.what());
+  }
+
+  return "";
+}//string TerminalModel::setYRange(string)
+
+
 // Command: searchpeak - does the work of double-clicking a peak inside the spectrum
 // Syntax: searchpeak( x )
 // Return value: none, basically highlights a peak on the spectrum and outputs whether or not it was successful or not