ENH: add correspondence from index to classlabel in ConfusionMatrixCalculator

Code/Learning/otbConfusionMatrixCalculator.h

@@ -97,11 +97,22 @@ public:
   itkGetMacro(NumberOfSamples, unsigned long);
   itkGetMacro(ConfusionMatrix, ConfusionMatrixType);
 
+  /* Gives the correspondence between a class label
+   * and its index in the confusion matrix
+   */
   std::map<ClassLabelType, int> GetMapOfClasses() const
   {
     return m_MapOfClasses;
   }
 
+  /* Gives the correspondence between an index in the
+   * confusion matrix and the class label
+   */
+  std::map<int, ClassLabelType> GetMapOfIndices() const
+  {
+    return m_MapOfIndices;
+  }
+
 protected:
   ConfusionMatrixCalculator();
   virtual ~ConfusionMatrixCalculator() {}
@@ -136,6 +147,7 @@ private:
   double m_FScore;
 
   std::map<ClassLabelType, int> m_MapOfClasses;
+  std::map<int, ClassLabelType> m_MapOfIndices;
 
   unsigned short m_NumberOfClasses;
   unsigned long  m_NumberOfSamples;

Code/Learning/otbConfusionMatrixCalculator.txx

@@ -77,15 +77,14 @@ ConfusionMatrixCalculator<TRefListLabel, TProdListLabel>
   int countClasses = 0;
   while (refIterator != m_ReferenceLabels->End())
     {
-
     int currentLabel = refIterator.GetMeasurementVector()[0];
     if (m_MapOfClasses.find(currentLabel) == m_MapOfClasses.end())
       {
       m_MapOfClasses[currentLabel] = countClasses;
+      m_MapOfIndices[countClasses] = currentLabel;
       ++countClasses;
       }
     ++refIterator;
-
     }
 
   m_NumberOfClasses = countClasses;