Changeset 1122

Timestamp:

Feb 22, 2008, 6:01:15 PM (16 years ago)

Author:

Peter

Message:

refs #335 - Changed so Averager classes are consistently returning NaN when Averager is empty or for some other reason the estimation ends up with things like zero by zero division. Previously zero was returned from some functions and Nan from some functions. I did not change anythuing in NCC.

Location:

trunk

Files:

• test/Makefile.am (modified) (1 diff)
• yat/statistics/Averager.cc (modified) (3 diffs)
• yat/statistics/Averager.h (modified) (1 diff)
• yat/statistics/AveragerPair.cc (modified) (1 diff)
• yat/statistics/AveragerPair.h (modified) (1 diff)
• yat/statistics/AveragerPairWeighted.cc (modified) (2 diffs)
• yat/statistics/AveragerPairWeighted.h (modified) (1 diff)
• yat/statistics/AveragerWeighted.cc (modified) (1 diff)

trunk/test/Makefile.am

@@ -33 +33 @@
   ensemble_test feature_selection_test fileutil_test \
   index_test inputranker_test \
-  iterator_test kernel_test kernel_lookup_test \
-  knn_test matrix_test matrix_lookup_test \
+  iterator_test kernel_lookup_test kernel_test \
+  knn_test matrix_lookup_test matrix_test \
   nbc_test \
   ncc_test nni_test pca_test regression_test rnd_test roc_test \

trunk/yat/statistics/Averager.cc

@@ -26 +26 @@
 
 #include <cassert>
+#include <limits>
 
 namespace theplu {
@@ -56 +57 @@
   double Averager::cv(void) const
   {
-    return x_ ? std()/mean() : 0;
+    return std()/mean();
   }
 
   double Averager::mean(void) const
   {
-    return n_ ? x_/n_ : 0;
+    return x_/n_;
   }
 
@@ -113 +114 @@
   double Averager::variance(double m) const
   {
-    return n_ ? (xx_ - 2*m*x_ + m*m*n()) /n_ : 0;
+    return (xx_ - 2*m*x_ + m*m*n()) /n_;
   }
 
   double Averager::variance(void) const
   {
-    return n_>1 ? sum_xx_centered()/n_ : 0;
+    return sum_xx_centered()/n_;
   }
 
   double Averager::variance_unbiased(void) const
   {
-    return (n_>1) ? sum_xx_centered()/(n_-1) : 0;
+    return (n_>1) ? sum_xx_centered()/(n_-1) : 
+      std::numeric_limits<double>::quiet_NaN();
   }
 

trunk/yat/statistics/Averager.h

@@ -143 +143 @@
     double variance(double m) const;
 
-    ///
-    /// @brief The estimated variance
-    ///
-    /// The variance is calculated as \f$ \frac{1}{N}\sum_i
-    /// (x_i-m)^2 \f$, where \f$ m \f$ is the mean.
-    ///
-    /// @return Estimation of variance
-    ///
+    /**
+       \brief The estimated variance
+       
+       The variance is calculated as \f$ \frac{1}{N}\sum_i
+       (x_i-m)^2 \f$, where \f$ m \f$ is the mean.
+       
+       \return Estimation of variance
+    */
     double variance(void) const;
 

trunk/yat/statistics/AveragerPair.cc

@@ -51 +51 @@
   double AveragerPair::ccc(void) const
   {
-    return ( (x_.variance() && y_.variance() && (x_.mean()-y_.mean()) ) ?
-             ((2*covariance()) /
-              ((x_.variance()+y_.variance()) +
-               (x_.mean()-y_.mean())*(x_.mean()-y_.mean()))) : 0);
+    return ((2*covariance()) /
+            ((x_.variance()+y_.variance()) +
+             (x_.mean()-y_.mean())*(x_.mean()-y_.mean())));
   }
 
   double AveragerPair::correlation(void) const
-  { return ((x_.std()>0 && y_.std()>0) ?
-            (covariance() / (x_.std()*y_.std()) ) : 0);
+  { return covariance() / std::sqrt(x_.variance()*y_.variance());
   }
 
   double AveragerPair::covariance(void) const
   {
-    return (n()>1) ? (xy_ - x_.sum_x()*y_.mean()) / n(): 0;
+    return (xy_ - x_.sum_x()*y_.mean()) / n();
   }
 

trunk/yat/statistics/AveragerPair.h

@@ -73 +73 @@
        \f$ \frac{\sum_i (x_i-m_x)(y_i-m_y)}{\sum_i
        (x_i-m_x)^2+\sum_i (y_i-m_y)^2 + n(m_x-m_y)^2} \f$ 
-       
-       In case of a zero denominator - zero is returned.
        
        @return Concordence correlation coefficient.

trunk/yat/statistics/AveragerPairWeighted.cc

@@ -27 +27 @@
 #include "AveragerPair.h"
 #include "Averager.h"
-#include "yat/classifier/DataLookup1D.h"
-#include "yat/classifier/DataLookupWeighted1D.h"
 
 #include <cassert>
@@ -63 +61 @@
   double AveragerPairWeighted::correlation(void) const
   {
-    return ( x_.variance()>0 && y_.variance()>0 ? 
-             covariance() / sqrt(x_.variance()*y_.variance()) : 0 );
+    return covariance() / sqrt(x_.variance()*y_.variance());
   }
 

trunk/yat/statistics/AveragerPairWeighted.h

@@ -37 +37 @@
 namespace theplu{
 namespace yat{
-namespace classifier{
-  class DataLookup1D;
-  class DataLookupWeighted1D;
-}
 namespace statistics{
   ///

trunk/yat/statistics/AveragerWeighted.cc

@@ -52 +52 @@
   double AveragerWeighted::mean(void) const
   {
-    return sum_w() ? sum_wx()/sum_w() : 0;
+    return sum_wx()/sum_w();
   }