1 files changed, 135 insertions, 0 deletions
diff --git a/src/de/lmu/ifi/dbs/elki/datasource/filter/AbstractFeatureSelectionFilter.java b/src/de/lmu/ifi/dbs/elki/datasource/filter/AbstractFeatureSelectionFilter.java
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+package de.lmu.ifi.dbs.elki.datasource.filter;
+/*
+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.BitSet;
+import java.util.List;
+
+import de.lmu.ifi.dbs.elki.data.FeatureVector;
+import de.lmu.ifi.dbs.elki.data.NumberVector;
+import de.lmu.ifi.dbs.elki.utilities.optionhandling.AbstractParameterizer;
+import de.lmu.ifi.dbs.elki.utilities.optionhandling.OptionID;
+import de.lmu.ifi.dbs.elki.utilities.optionhandling.constraints.ListGreaterEqualConstraint;
+import de.lmu.ifi.dbs.elki.utilities.optionhandling.parameterization.Parameterization;
+import de.lmu.ifi.dbs.elki.utilities.optionhandling.parameters.IntListParameter;
+
+/**
+ * <p>
+ * A ProjectionParser projects the objects of its base parser onto a subspace
+ * specified by a BitSet.
+ * </p>
+ * 
+ * @author Arthur Zimek
+ * @author Erich Schubert
+ * @param <V> the type of FeatureVector contained in both the original and
+ *        projected data.
+ */
+public abstract class AbstractFeatureSelectionFilter<V extends FeatureVector<?, ?>> extends AbstractConversionFilter<V, V> {
+  /**
+   * <p>
+   * Selected attributes parameter.
+   * </p>
+   * <p>
+   * Key: <code>-projectionfilter.selectedattributes</code>
+   * </p>
+   */
+  public static final OptionID SELECTED_ATTRIBUTES_ID = OptionID.getOrCreateOptionID("projectionfilter.selectedattributes", "a comma separated array of integer values d_i, where 1 <= d_i <= the " + "dimensionality of the feature space " + "specifying the dimensions to be considered " + "for projection. If this parameter is not set, " + "no dimensions will be considered, i.e. the projection is a zero-dimensional feature space");
+
+  /**
+   * Keeps the selection of the subspace to project onto.
+   */
+  private BitSet selectedAttributes;
+
+  /**
+   * Constructor.
+   * 
+   * @param selectedAttributes
+   */
+  public AbstractFeatureSelectionFilter(BitSet selectedAttributes) {
+    super();
+    this.selectedAttributes = selectedAttributes;
+  }
+
+  /**
+   * <p>
+   * Sets the bits set to true in the given BitSet as selected attributes in
+   * {@link #SELECTED_ATTRIBUTES_ID}.
+   * </p>
+   * 
+   * The index in the BitSet is expected to be shifted to the left by one, i.e.,
+   * index 0 in the BitSet relates to the first attribute.
+   * 
+   * @param selectedAttributes the new selected attributes
+   */
+  public void setSelectedAttributes(BitSet selectedAttributes) {
+    this.selectedAttributes.or(selectedAttributes);
+  }
+
+  /**
+   * <p>
+   * Provides a BitSet with the bits set to true corresponding to the selected
+   * attributes in {@link #SELECTED_ATTRIBUTES_ID}.
+   * </p>
+   * 
+   * The index in the BitSet is shifted to the left by one, i.e., index 0 in the
+   * BitSet relates to the first attribute.
+   * 
+   * @return the selected attributes
+   */
+  public BitSet getSelectedAttributes() {
+    return selectedAttributes;
+  }
+
+  /**
+   * Get the resulting dimensionality.
+   * 
+   * @return dimensionality
+   */
+  public int getDimensionality() {
+    return selectedAttributes.cardinality();
+  }
+
+  /**
+   * Parameterization class.
+   * 
+   * @author Erich Schubert
+   * 
+   * @apiviz.exclude
+   */
+  public static abstract class Parameterizer<V extends NumberVector<V, ?>> extends AbstractParameterizer {
+    protected BitSet selectedAttributes = null;
+
+    @Override
+    protected void makeOptions(Parameterization config) {
+      super.makeOptions(config);
+      IntListParameter selectedAttributesP = new IntListParameter(SELECTED_ATTRIBUTES_ID, new ListGreaterEqualConstraint<Integer>(1));
+      if(config.grab(selectedAttributesP)) {
+        selectedAttributes = new BitSet();
+        List<Integer> dimensionList = selectedAttributesP.getValue();
+        for(int d : dimensionList) {
+          selectedAttributes.set(d - 1);
+        }
+      }
+    }
+  }
+}
+\ No newline at end of file