verbose flag for MutualInformation

cbaselib/MutualInformation.cpp

@@ -17,8 +17,9 @@ using namespace NICE;
 
 
 
-MutualInformation::MutualInformation()
+MutualInformation::MutualInformation( bool verbose )
 {
+  this->verbose = verbose;
 }
 
 MutualInformation::~MutualInformation()
@@ -155,47 +156,41 @@ double MutualInformation::computeThresholdClass ( const LabeledSetVector & ls, s
 double MutualInformation::computeThresholdOverall ( const LabeledSetVector & ls, size_t dimension, double & opt_threshold ) const
 {
   vector<double> thresholds;
+  vector<int> y;
   LOOP_ALL(ls)
   {
     EACH(classno, v);
     double val = v[dimension];
     thresholds.push_back ( val );
+    y.push_back(classno);
   }
   sort ( thresholds.begin(), thresholds.end() );
   thresholds.erase( std::unique( thresholds.begin(), thresholds.end()), thresholds.end());
   
   opt_threshold = 0.0;
   double opt_mi = 0.0;
-#ifdef DEBUGMUTUALINFORMATION
-  vector<double> x;
-  vector<double> y;
-#endif
 
+  uint ind = 0;
   for ( vector<double>::const_iterator i  = thresholds.begin();
-               i != thresholds.end(); 
-         i++ )
+               i != thresholds.end(); i++, ind++ )
   {
     vector<double>::const_iterator j = i + 1;
     if ( j == thresholds.end() ) break;
 
+    // the optimimum can not be found at non-class borders
+    if ( y[ind] == y[ind+1] ) continue;
+
     double threshold = 0.5 * ((*i) + (*j));
+
+    // FIXME: This call is pretty inefficient!!
+    // We can directly count the features here...might be 100times faster :)
     double mi = mutualInformationOverall ( ls, dimension, threshold );
-#ifdef DEBUGMUTUALINFORMATION
-    x.push_back ( threshold );
-    y.push_back ( mi );
-#endif
     if ( mi > opt_mi ) {
         opt_mi = mi;
         opt_threshold = threshold;
     }
   }
    
-#ifdef DEBUGMUTUALINFORMATION
-  if ( x.size() > 0 ) 
-    Gnuplot gnu ( "Mutual Information", "smooth csplines", "threshold", 
-     "mi", x, y );
-#endif
-
   return opt_mi;
 }
 
@@ -204,14 +199,15 @@ void MutualInformation::computeThresholdsClass ( const LabeledSetVector & ls, si
 {
   size_t max_dimension = ls.dimension();
 
-  thresholds.clear();
-  mis.clear();
+  thresholds.resize(max_dimension);
+  mis.resize(max_dimension);
+
   for ( size_t k = 0 ; k < max_dimension ; k++ )
   {
     double t, mi;
     mi = computeThresholdClass ( ls, classno, k, t );
-    mis.append(mi);
-    thresholds.append(t);
+    mis[k] = mi;
+    thresholds[k] = t;
   }
 }
 
@@ -219,13 +215,15 @@ void MutualInformation::computeThresholdsOverall ( const LabeledSetVector & ls,
 {
   size_t max_dimension = ls.dimension();
 
-  thresholds.clear();
-  mis.clear();
+  thresholds.resize(max_dimension);
+  mis.resize(max_dimension);
   for ( size_t k = 0 ; k < max_dimension ; k++ )
   {
+    if ( verbose )
+      cerr << "MutualInformation: Optimizing threshold for feature " << k << " / " << max_dimension << endl;
     double t, mi;
     mi = computeThresholdOverall ( ls, k, t );
-    mis.append(mi);
-    thresholds.append(t);
+    mis[k] = mi;
+    thresholds[k] = t;
   }
 }

cbaselib/MutualInformation.h

@@ -17,8 +17,11 @@ namespace OBJREC {
 /** Part selection and thresholding with mutual information */
 class MutualInformation
 {
-
   protected:
+
+    //! verbose handling
+    bool verbose;
+
     /**
     * @brief helper function: loop through all vectors and count how often f[d]>threshold
     *
@@ -43,7 +46,7 @@ class MutualInformation
   public:
   
     /** simple constructor */
-    MutualInformation();
+    MutualInformation( bool verbose = false );
         
     /** simple destructor */
     virtual ~MutualInformation();