Author: srowen
Date: Mon Dec 5 20:13:43 2011
New Revision: 1210603
URL: http://svn.apache.org/viewvc?rev=1210603&view=rev
Log:
MAHOUT-902 oops do not return NaN from distributed item-item simliarity as 0
means 'ignore'
Modified:
mahout/trunk/core/src/main/java/org/apache/mahout/math/hadoop/similarity/cooccurrence/measures/TanimotoCoefficientSimilarity.java
Modified:
mahout/trunk/core/src/main/java/org/apache/mahout/math/hadoop/similarity/cooccurrence/measures/TanimotoCoefficientSimilarity.java
URL:
http://svn.apache.org/viewvc/mahout/trunk/core/src/main/java/org/apache/mahout/math/hadoop/similarity/cooccurrence/measures/TanimotoCoefficientSimilarity.java?rev=1210603&r1=1210602&r2=1210603&view=diff
==============================================================================
---
mahout/trunk/core/src/main/java/org/apache/mahout/math/hadoop/similarity/cooccurrence/measures/TanimotoCoefficientSimilarity.java
(original)
+++
mahout/trunk/core/src/main/java/org/apache/mahout/math/hadoop/similarity/cooccurrence/measures/TanimotoCoefficientSimilarity.java
Mon Dec 5 20:13:43 2011
@@ -21,7 +21,8 @@ public class TanimotoCoefficientSimilari
@Override
public double similarity(double dots, double normA, double normB, int
numberOfColumns) {
- return dots == 0 ? Double.NaN : dots / (normA + normB - dots);
+ // Return 0 even when dots == 0 since this will cause it to be ignored --
not NaN
+ return dots / (normA + normB - dots);
}
@Override
