Changeset 37 for trunk/src/SVM.cc

Timestamp:

Feb 13, 2004, 4:46:31 PM (19 years ago)

Author:

Peter

Message:

SVM.get_output added

File:

• trunk/src/SVM.cc (modified) (4 diffs)

trunk/src/SVM.cc

@@ -20 +20 @@
                  kernel_(kernel),
                  target_(target),
-                 alpha_(target.size(),true,true)
+                 alpha_(target.size(),true,true),
+                 bias_(0)
+  
 {
 }
@@ -38 +40 @@
   // Stop criteria  
   bool stop_condition = false;
-  while(count<100000 && !stop_condition)
+  while(!stop_condition)
     {
      count++;  
@@ -90 +92 @@
      alpha_[index2]=alpha_new;
      stop_condition = stop( target_, kernel_, alpha_);
+     if (count>10000000){
+      cerr << "SVM): " << "more than 10,000,000 epochs reached" << endl;
+       exit(1);
+     }
     }
+
+  // Calculating the bias
+  double min_output_positive = 10000;
+  double max_output_negative = -10000;
+  thep_gsl_api::vector output_unbiased = kernel_ * alpha_.mul_elements(target_);
+  for (u_int i=0; i<target_.size(); i++){
+   if (target_[i]==1){
+     if (output_unbiased[i] < min_output_positive)
+       min_output_positive = output_unbiased[i];
+   }
+   else if( output_unbiased[i] > max_output_negative )
+     max_output_negative = output_unbiased[i];
   
+  }
+  cout << max_output_negative << endl;
+  cout << min_output_positive << endl;
+  
+  bias_ = ( -min_output_positive - max_output_negative )/2;
+  cout << "bias:" << bias_ << endl;
+
   trained_= true;
 }
@@ -101 +126 @@
   double min_output_positive = 10000;
   double max_output_negative = -10000;
-  double epsilon = 0.001; // used twice, should perhaps be two different values
+  double epsilon = 0.000001; // used twice, should perhaps be two different values
   thep_gsl_api::vector output_unbiased = kernel_ * alpha_.mul_elements(target_);
   for (u_int i=0; i<target_.size(); i++){