1 files changed, 116 insertions, 0 deletions
diff --git a/src/de/lmu/ifi/dbs/elki/evaluation/scores/adapter/DecreasingVectorIter.java b/src/de/lmu/ifi/dbs/elki/evaluation/scores/adapter/DecreasingVectorIter.java
new file mode 100644
index 00000000..d0a55b19
--- /dev/null
+++ b/src/de/lmu/ifi/dbs/elki/evaluation/scores/adapter/DecreasingVectorIter.java
@@ -0,0 +1,116 @@
+package de.lmu.ifi.dbs.elki.evaluation.scores.adapter;
+
+/*
+ This file is part of ELKI:
+ Environment for Developing KDD-Applications Supported by Index-Structures
+
+ Copyright (C) 2014
+ 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 de.lmu.ifi.dbs.elki.data.NumberVector;
+import de.lmu.ifi.dbs.elki.evaluation.scores.ScoreEvaluation.ScoreIter;
+import de.lmu.ifi.dbs.elki.utilities.datastructures.arrays.IntegerArrayQuickSort;
+import de.lmu.ifi.dbs.elki.utilities.datastructures.arrays.IntegerComparator;
+import de.lmu.ifi.dbs.elki.utilities.datastructures.iterator.ArrayIter;
+
+/**
+ * Class to iterate over a number vector in decreasing order.
+ * 
+ * @author Erich Schubert
+ * 
+ * @apiviz.composedOf NumberVector
+ */
+public class DecreasingVectorIter implements ScoreIter, IntegerComparator, ArrayIter {
+  /**
+   * Order of dimensions.
+   */
+  private int[] sort;
+
+  /**
+   * Data vector.
+   */
+  private NumberVector vec;
+
+  /**
+   * Current position.
+   */
+  int pos = 0;
+
+  /**
+   * Constructor.
+   * 
+   * @param vec Vector to iterate over.
+   */
+  public DecreasingVectorIter(NumberVector vec) {
+    this.vec = vec;
+    final int dim = vec.getDimensionality();
+    this.sort = new int[dim];
+    for(int d = 0; d < dim; d++) {
+      sort[d] = d;
+    }
+    IntegerArrayQuickSort.sort(sort, this);
+  }
+
+  @Override
+  public int compare(int x, int y) {
+    return Double.compare(vec.doubleValue(y), vec.doubleValue(x));
+  }
+
+  public int dim() {
+    return sort[pos];
+  }
+
+  @Override
+  public boolean valid() {
+    return pos < vec.getDimensionality() && pos >= 0;
+  }
+
+  @Override
+  public DecreasingVectorIter advance() {
+    ++pos;
+    return this;
+  }
+
+  @Override
+  public boolean tiedToPrevious() {
+    return pos > 0 && Double.compare(vec.doubleValue(sort[pos]), vec.doubleValue(sort[pos - 1])) == 0;
+  }
+
+  @Override
+  public int getOffset() {
+    return pos;
+  }
+
+  @Override
+  public DecreasingVectorIter advance(int count) {
+    pos += count;
+    return this;
+  }
+
+  @Override
+  public DecreasingVectorIter retract() {
+    pos--;
+    return this;
+  }
+
+  @Override
+  public DecreasingVectorIter seek(int off) {
+    pos = off;
+    return this;
+  }
+}
+\ No newline at end of file