1 files changed, 132 insertions, 0 deletions
diff --git a/src/de/lmu/ifi/dbs/elki/utilities/datastructures/histogram/IntStaticHistogram.java b/src/de/lmu/ifi/dbs/elki/utilities/datastructures/histogram/IntStaticHistogram.java
new file mode 100644
index 00000000..d4de36d7
--- /dev/null
+++ b/src/de/lmu/ifi/dbs/elki/utilities/datastructures/histogram/IntStaticHistogram.java
@@ -0,0 +1,132 @@
+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) 2012
+ 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.Arrays;
+
+/**
+ * Histogram class storing int values.
+ * 
+ * The histogram will start with "bin" bins, but it can grow dynamically to the
+ * left and right.
+ * 
+ * @author Erich Schubert
+ */
+public class IntStaticHistogram extends AbstractStaticHistogram implements IntHistogram {
+  /**
+   * Constructor.
+   * 
+   * @param bins Number of bins
+   * @param min Cover minimum
+   * @param max Cover maximum
+   */
+  public IntStaticHistogram(int bins, double min, double max) {
+    super(bins, min, max);
+    if (bins >= 0) {
+      data = new int[bins];
+    } else {
+      data = null;
+    }
+  }
+
+  /**
+   * Data store
+   */
+  int[] data;
+
+  /**
+   * Increment the value of a bin.
+   * 
+   * @param coord Coordinate
+   * @param val Value
+   */
+  @Override
+  public void increment(double coord, int val) {
+    int bin = getBinNr(coord);
+    if (bin < 0) {
+      if (size - bin > data.length) {
+        // Reallocate. TODO: use an arraylist-like grow strategy!
+        int[] tmpdata = new int[growSize(data.length, size - bin)];
+        System.arraycopy(data, 0, tmpdata, -bin, size);
+        data = tmpdata;
+      } else {
+        // Shift in place and clear head
+        System.arraycopy(data, 0, data, -bin, size);
+        Arrays.fill(data, 0, -bin, (int) 0);
+      }
+      data[0] = val;
+      // Note that bin is negative, -bin is the shift offset!
+      assert (data.length >= size - bin);
+      offset -= bin;
+      size -= bin;
+      // TODO: modCounter++; and have iterators fast-fail
+    } else if (bin >= data.length) {
+      int[] tmpdata = new int[growSize(data.length, bin + 1)];
+      System.arraycopy(data, 0, tmpdata, 0, size);
+      tmpdata[bin] = val;
+      data = tmpdata;
+      size = bin + 1;
+      // TODO: modCounter++; and have iterators fast-fail
+      // Unset max value when resizing
+      max = Double.MAX_VALUE;
+    } else {
+      if (bin >= size) {
+        // TODO: reset bins to 0 first?
+        size = bin + 1;
+      }
+      data[bin] += val;
+    }
+  }
+
+  /**
+   * Get the value at a particular position.
+   * 
+   * @param coord Coordinate
+   * @return Value
+   */
+  public int get(double coord) {
+    int bin = getBinNr(coord);
+    if (bin < 0 || bin >= size) {
+      return 0;
+    }
+    return data[bin];
+  }
+
+  @Override
+  public Iter iter() {
+    return new Iter();
+  }
+
+  /**
+   * Iterator class.
+   * 
+   * @author Erich Schubert
+   */
+  public class Iter extends AbstractStaticHistogram.Iter implements IntHistogram.Iter {
+    @Override
+    public int getValue() {
+      return data[bin];
+    }
+  }
+}