Changeset 157

Timestamp:

Sep 16, 2004, 1:55:22 AM (19 years ago)

Author:

Jari Häkkinen

Message:

Changed algorithm to make no impute on values if no contributions exists.
This is the case when all weights are zero for a row or weights are zero
in for rows in such a way that they cancel out.
Changed the test data files acordingly.

Location:

trunk

Files:

• src/WeNNI.cc (modified) (1 diff)
• src/kNNI.cc (modified) (1 diff)
• test/data/knni_matrix.data (added)
• test/data/knni_result.data (added)
• test/data/knni_weight.data (added)
• test/data/wenni_result.data (added)
• test/data/wenni_weight.data (added)

trunk/src/WeNNI.cc

@@ -40 +40 @@
           norm+=1.0/(distance[*k].second);
         }
-        data_(i,j)=weight_(i,j)*data_(i,j)+(1-weight_(i,j))*new_value/norm;
+        // No impute if no contributions from neighbours.
+        if (norm)
+          data_(i,j)=weight_(i,j)*data_(i,j)+(1-weight_(i,j))*new_value/norm;
       }
     }

trunk/src/kNNI.cc

@@ -47 +47 @@
             norm+=1.0/(distance[*k].second);
           }
-          data_(mv_rows_[i],j)=new_value/norm;
+          // No impute if no contributions from neighbours.
+          if (norm)
+            data_(mv_rows_[i],j)=new_value/norm;
         }
     }