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diff --git a/src/de/lmu/ifi/dbs/elki/data/Bit.java b/src/de/lmu/ifi/dbs/elki/data/Bit.java
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+++ b/src/de/lmu/ifi/dbs/elki/data/Bit.java
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+package de.lmu.ifi.dbs.elki.data;
+/*
+This file is part of ELKI:
+Environment for Developing KDD-Applications Supported by Index-Structures
+
+Copyright (C) 2011
+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/>.
+*/
+
+import java.util.regex.Pattern;
+
+/**
+ * Provides a bit number. The bit is internally represented as boolean.
+ * 
+ * @author Arthur Zimek
+ */
+public class Bit extends Number {
+  /**
+   * Generated serial version UID.
+   */
+  private static final long serialVersionUID = 390879869314931240L;
+
+  /**
+   * Pattern defining valid bit values. A valid bit value is either 0 or 1.
+   */
+  public static final Pattern BIT_PATTERN = Pattern.compile("^[01]$");
+
+  /**
+   * Method to construct a Bit for a given String expression.
+   * 
+   * @param bit a String expression defining a Bit
+   * @return a Bit as defined by the given String expression
+   * @throws NumberFormatException if the given String expression does not fit
+   *         to the Pattern {@link #BIT_PATTERN BIT_PATTERN}
+   */
+  public static Bit valueOf(String bit) throws NumberFormatException {
+    if(!BIT_PATTERN.matcher(bit).matches()) {
+      throw new NumberFormatException("Input \"" + bit + "\" does not fit required pattern: " + BIT_PATTERN.pattern());
+    }
+    return new Bit(Integer.parseInt(bit));
+  }
+
+  /**
+   * Internal representation of the bit value.
+   */
+  private boolean bit;
+
+  /**
+   * Provides a new bit according to the specified boolean value.
+   * 
+   * @param bit the boolean value of this bit
+   */
+  public Bit(boolean bit) {
+    this.bit = bit;
+  }
+
+  /**
+   * Provides a new bit according to the specified integer value. The bit value
+   * is 1 for true and 0 for false.
+   * 
+   * @param bit 1 for true and 0 for false
+   * @throws IllegalArgumentException if the specified value is neither 0 nor 1.
+   */
+  public Bit(int bit) throws IllegalArgumentException {
+    if(bit != 0 && bit != 1) {
+      throw new IllegalArgumentException("Required: 0 or 1 - found: " + bit);
+    }
+    this.bit = bit == 1;
+  }
+
+  /**
+   * Provides an integer representation of the bit.
+   * 
+   * @return 1 if the bit is set, 0 otherwise
+   */
+  @Override
+  public int intValue() {
+    return bit ? 1 : 0;
+  }
+
+  /**
+   * Provides a long value for the integer representation of this Bit as given
+   * by {@link #intValue() intValue()}.
+   */
+  @Override
+  public long longValue() {
+    return intValue();
+  }
+
+  /**
+   * Provides a float value for the integer representation of this Bit as given
+   * by {@link #intValue() intValue()}.
+   */
+  @Override
+  public float floatValue() {
+    return intValue();
+  }
+
+  /**
+   * Provides a double value for the integer representation of this Bit as given
+   * by {@link #intValue() intValue()}.
+   */
+  @Override
+  public double doubleValue() {
+    return intValue();
+  }
+
+  /**
+   * Returns the bit value as a boolean.
+   * 
+   * @return the bit value
+   */
+  public boolean bitValue() {
+    return this.bit;
+  }
+
+  /**
+   * Provides the String representation of the integer representation of this
+   * Bit as given by {@link #intValue() intValue()}.
+   * 
+   * @see java.lang.Object#toString()
+   */
+  @Override
+  public String toString() {
+    return Integer.toString(intValue());
+  }
+}