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diff --git a/elki/src/main/java/de/lmu/ifi/dbs/elki/utilities/datastructures/histogram/AbstractStaticHistogram.java b/elki/src/main/java/de/lmu/ifi/dbs/elki/utilities/datastructures/histogram/AbstractStaticHistogram.java
new file mode 100644
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--- /dev/null
+++ b/elki/src/main/java/de/lmu/ifi/dbs/elki/utilities/datastructures/histogram/AbstractStaticHistogram.java
@@ -0,0 +1,224 @@
+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) 2015
+ Ludwig-Maximilians-Universität München
+ Lehr- und Forschungseinheit für Datenbanksysteme
+ ELKI Development Team
+
+ This program is free software: you can redistribute it and/or modify
+ it under the terms of the GNU Affero General Public License as published by
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU Affero General Public License for more details.
+
+ You should have received a copy of the GNU Affero General Public License
+ along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+
+/**
+ * Abstract base class for histograms.
+ * 
+ * Note that this is abstracted from the actual data storage, so it can be
+ * adapted for multiple use cases.
+ * 
+ * @author Erich Schubert
+ */
+public abstract class AbstractStaticHistogram implements Histogram {
+  /**
+   * Array shift to account for negative indices.
+   */
+  protected int offset = 0;
+
+  /**
+   * Size of array storage.
+   */
+  protected int size;
+
+  /**
+   * Array 'base', i.e. the point of 0.0. Usually the minimum.
+   */
+  protected double base;
+
+  /**
+   * To avoid introducing an extra bucket for the maximum value.
+   */
+  protected double max;
+
+  /**
+   * Width of a bin.
+   */
+  protected double binsize;
+
+  /**
+   * Histogram constructor
+   * 
+   * @param bins Number of bins to use.
+   * @param min Minimum Value
+   * @param max Maximum Value
+   */
+  public AbstractStaticHistogram(int bins, double min, double max) {
+    this.base = min;
+    this.max = max;
+    this.binsize = (max - min) / bins;
+    this.size = bins;
+  }
+
+  /**
+   * Compute the bin number. Has a special case for rounding max down to the
+   * last bin.
+   * 
+   * @param coord Coordinate
+   * @return bin number
+   */
+  protected int getBinNr(double coord) {
+    if (Double.isInfinite(coord) || Double.isNaN(coord)) {
+      throw new UnsupportedOperationException("Encountered non-finite value in Histogram: " + coord);
+    }
+    if (coord == max) {
+      // System.err.println("Triggered special case: "+ (Math.floor((coord -
+      // base) / binsize) + offset) + " vs. " + (size - 1));
+      return size - 1;
+    }
+    return (int) Math.floor((coord - base) / binsize) + offset;
+  }
+
+  /**
+   * Compute the size to grow to.
+   * 
+   * @param current Current size
+   * @param requiredSize Required size
+   * @return Size to allocate
+   */
+  protected static int growSize(int current, int requiredSize) {
+    // Double until 64, then increase by 50% each time.
+    int newCapacity = ((current < 64) ? ((current + 1) << 1) : ((current >> 1) * 3));
+    // overflow?
+    if (newCapacity < 0) {
+      throw new OutOfMemoryError();
+    }
+    if (requiredSize > newCapacity) {
+      newCapacity = requiredSize;
+    }
+    return requiredSize;
+  }
+  
+  /**
+   * Get the number of bins actually in use.
+   * 
+   * @return number of bins
+   */
+  @Override
+  public int getNumBins() {
+    return size;
+  }
+
+  /**
+   * Get the size (width) of a bin.
+   * 
+   * @return bin size
+   */
+  @Override
+  public double getBinsize() {
+    return binsize;
+  }
+
+  /**
+   * Get minimum (covered by bins, not data!)
+   * 
+   * @return minimum
+   */
+  @Override
+  public double getCoverMinimum() {
+    return base - offset * binsize;
+  }
+
+  /**
+   * Get maximum (covered by bins, not data!)
+   * 
+   * @return maximum
+   */
+  @Override
+  public double getCoverMaximum() {
+    return base + (size - offset) * binsize;
+  }
+
+  /**
+   * Get an iterator over all histogram bins.
+   * 
+   * @return Iterator
+   */
+  @Override
+  public abstract Iter iter();
+
+  /**
+   * Iterator class to iterate over all bins.
+   * 
+   * @author Erich Schubert
+   * 
+   * @apiviz.exclude
+   */
+  public abstract class Iter implements Histogram.Iter {
+    /**
+     * Current bin number
+     */
+    int bin = 0;
+
+    @Override
+    public double getCenter() {
+      return base + (bin + 0.5 - offset) * binsize;
+    }
+
+    @Override
+    public double getLeft() {
+      return base + (bin - offset) * binsize;
+    }
+
+    @Override
+    public double getRight() {
+      return base + (bin + 1 - offset) * binsize;
+    }
+
+    @Override
+    public boolean valid() {
+      return bin >= 0 && bin < size;
+    }
+
+    @Override
+    public Iter advance() {
+      bin++;
+      return this;
+    }
+
+    @Override
+    public int getOffset() {
+      return bin;
+    }
+
+    @Override
+    public Iter advance(int count) {
+      bin += count;
+      return this;
+    }
+
+    @Override
+    public Iter retract() {
+      bin--;
+      return this;
+    }
+
+    @Override
+    public Iter seek(int off) {
+      bin = off;
+      return this;
+    }
+  }
+}