fix BIRCH intercluster distance

andiwg · kno10 · commit 56fffd25d13f · 2025-10-10T17:12:56.000+02:00
diff --git a/elki-clustering/src/main/java/elki/index/tree/betula/distance/BIRCHAverageInterclusterDistance.java b/elki-clustering/src/main/java/elki/index/tree/betula/distance/BIRCHAverageInterclusterDistance.java
@@ -64,7 +64,7 @@ public double squaredDistance(NumberVector v, ClusterFeature ocf) {
     for(int d = 0; d < dim; d++) {
       sum += v.doubleValue(d) * cf.ls(d);
     }
-    sum = /* 1. * */ cf.sumdev() + cf.getWeight() * BIRCHCF.sumOfSquares(v) - 2 * sum;
+    sum = /* 1. * */ cf.sumOfSumOfSquares() + cf.getWeight() * BIRCHCF.sumOfSquares(v) - 2 * sum;
     return sum > 0 ? sum / cf.getWeight() : 0;
   }
 

Original file line number	Diff line number	Diff line change
`@@ -64,7 +64,7 @@ public double squaredDistance(NumberVector v, ClusterFeature ocf) {`
`64`	`64`	`for(int d = 0; d < dim; d++) {`
`65`	`65`	`sum += v.doubleValue(d) * cf.ls(d);`
`66`	`66`	`}`
`67`		`- sum = /* 1. * / cf.sumdev() + cf.getWeight() BIRCHCF.sumOfSquares(v) - 2 * sum;`
	`67`	`+ sum = /* 1. * / cf.sumOfSumOfSquares() + cf.getWeight() BIRCHCF.sumOfSquares(v) - 2 * sum;`
`68`	`68`	`return sum > 0 ? sum / cf.getWeight() : 0;`
`69`	`69`	`}`
`70`	`70`