1 files changed, 9 insertions, 5 deletions
diff --git a/src/de/lmu/ifi/dbs/elki/utilities/datastructures/histogram/AbstractStaticHistogram.java b/src/de/lmu/ifi/dbs/elki/utilities/datastructures/histogram/AbstractStaticHistogram.java
index 3363e61e..798e1d80 100644
--- a/src/de/lmu/ifi/dbs/elki/utilities/datastructures/histogram/AbstractStaticHistogram.java
+++ b/src/de/lmu/ifi/dbs/elki/utilities/datastructures/histogram/AbstractStaticHistogram.java
@@ -4,7 +4,7 @@ package de.lmu.ifi.dbs.elki.utilities.datastructures.histogram;
  This file is part of ELKI:
  Environment for Developing KDD-Applications Supported by Index-Structures
 
- Copyright (C) 2013
+ Copyright (C) 2014
  Ludwig-Maximilians-Universität München
  Lehr- und Forschungseinheit für Datenbanksysteme
  ELKI Development Team
@@ -193,8 +193,9 @@ public abstract class AbstractStaticHistogram implements Histogram {
     }
 
     @Override
-    public void advance() {
+    public Iter advance() {
       bin++;
+      return this;
     }
 
     @Override
@@ -203,18 +204,21 @@ public abstract class AbstractStaticHistogram implements Histogram {
     }
 
     @Override
-    public void advance(int count) {
+    public Iter advance(int count) {
       bin += count;
+      return this;
     }
 
     @Override
-    public void retract() {
+    public Iter retract() {
       bin--;
+      return this;
     }
 
     @Override
-    public void seek(int off) {
+    public Iter seek(int off) {
       bin = off;
+      return this;
     }
   }
 }