예제 #1
0
  /**
   * Build one rule using the growing data
   *
   * @param data the growing data used to build the rule
   * @throws Exception if the consequent is not set yet
   */
  public void grow(Instances data) throws Exception {
    if (m_Consequent == -1) throw new Exception(" Consequent not set yet.");

    Instances growData = data;
    double sumOfWeights = growData.sumOfWeights();
    if (!Utils.gr(sumOfWeights, 0.0)) return;

    /* Compute the default accurate rate of the growing data */
    double defAccu = computeDefAccu(growData);
    double defAcRt = (defAccu + 1.0) / (sumOfWeights + 1.0);

    /* Keep the record of which attributes have already been used*/
    boolean[] used = new boolean[growData.numAttributes()];
    for (int k = 0; k < used.length; k++) used[k] = false;
    int numUnused = used.length;

    // If there are already antecedents existing
    for (int j = 0; j < m_Antds.size(); j++) {
      Antd antdj = (Antd) m_Antds.elementAt(j);
      if (!antdj.getAttr().isNumeric()) {
        used[antdj.getAttr().index()] = true;
        numUnused--;
      }
    }

    double maxInfoGain;
    while (Utils.gr(growData.numInstances(), 0.0) && (numUnused > 0) && Utils.sm(defAcRt, 1.0)) {

      // We require that infoGain be positive
      /*if(numAntds == originalSize)
      maxInfoGain = 0.0; // At least one condition allowed
      else
      maxInfoGain = Utils.eq(defAcRt, 1.0) ?
      defAccu/(double)numAntds : 0.0; */
      maxInfoGain = 0.0;

      /* Build a list of antecedents */
      Antd oneAntd = null;
      Instances coverData = null;
      Enumeration enumAttr = growData.enumerateAttributes();

      /* Build one condition based on all attributes not used yet*/
      while (enumAttr.hasMoreElements()) {
        AttributeWeka att = (AttributeWeka) (enumAttr.nextElement());

        if (m_Debug) System.err.println("\nOne condition: size = " + growData.sumOfWeights());

        Antd antd = null;
        if (att.isNumeric()) antd = new NumericAntd(att);
        else antd = new NominalAntd(att);

        if (!used[att.index()]) {
          /* Compute the best information gain for each attribute,
          it's stored in the antecedent formed by this attribute.
          This procedure returns the data covered by the antecedent*/
          Instances coveredData = computeInfoGain(growData, defAcRt, antd);
          if (coveredData != null) {
            double infoGain = antd.getMaxInfoGain();
            if (m_Debug)
              System.err.println(
                  "Test of \'"
                      + antd.toString()
                      + "\': infoGain = "
                      + infoGain
                      + " | Accuracy = "
                      + antd.getAccuRate()
                      + "="
                      + antd.getAccu()
                      + "/"
                      + antd.getCover()
                      + " def. accuracy: "
                      + defAcRt);

            if (infoGain > maxInfoGain) {
              oneAntd = antd;
              coverData = coveredData;
              maxInfoGain = infoGain;
            }
          }
        }
      }

      if (oneAntd == null) break; // Cannot find antds
      if (Utils.sm(oneAntd.getAccu(), m_MinNo)) break; // Too low coverage

      // Numeric attributes can be used more than once
      if (!oneAntd.getAttr().isNumeric()) {
        used[oneAntd.getAttr().index()] = true;
        numUnused--;
      }

      m_Antds.addElement(oneAntd);

      growData = coverData; // Grow data size is shrinking
      defAcRt = oneAntd.getAccuRate();
    }
  }
예제 #2
0
  /**
   * This function fits the rule to the data which it overlaps. This way the rule can only
   * interpolate but not extrapolate.
   *
   * @param instances The data to which the rule shall be fitted
   */
  public void fitAndSetCoreBound(Instances instances) {
    if (m_Antds == null) return;
    boolean[] antExistingForDimension = new boolean[instances.numAttributes() - 1];
    for (int i = 0; i < m_Antds.size(); i++) {
      antExistingForDimension[((Antd) m_Antds.elementAt(i)).att.index()] = true;
    }

    FastVector newAntds = new FastVector(10);
    //    for (int i=0; i < instances.numAttributes()-1; i++){
    for (int iterator = 0; iterator < m_Antds.size(); iterator++) {
      int i = ((Antd) m_Antds.elementAt(iterator)).getAttr().index();

      if (!antExistingForDimension[i]) continue; // Excluding non existant antecedents
      Instances instancesWithoutMissingValues = new Instances(instances);
      instancesWithoutMissingValues.deleteWithMissing(i);

      if (instancesWithoutMissingValues.attribute(i).isNumeric()
          && instancesWithoutMissingValues.numInstances() > 0) {
        boolean bag0AntdExists = false;
        boolean bag1AntdExists = false;
        for (int j = 0; j < m_Antds.size(); j++) {
          if (((Antd) m_Antds.elementAt(j)).att.index() == i) {
            if (((Antd) m_Antds.elementAt(j)).value == 0) {
              bag0AntdExists = true;
            } else {
              bag1AntdExists = true;
            }
            newAntds.addElement((Antd) m_Antds.elementAt(j));
          }
        }

        double higherCore = Double.NaN;
        double lowerCore = Double.NaN;

        if (!bag0AntdExists) {
          if (Double.isNaN(higherCore))
            higherCore =
                instancesWithoutMissingValues.kthSmallestValue(
                    i, instancesWithoutMissingValues.numInstances());
          NumericAntd antd;
          antd = new NumericAntd(instancesWithoutMissingValues.attribute(i));
          antd.value = 0;
          antd.splitPoint = higherCore;
          newAntds.addElement(antd);
        }

        if (!bag1AntdExists) {
          if (Double.isNaN(lowerCore))
            lowerCore = instancesWithoutMissingValues.kthSmallestValue(i, 1);
          NumericAntd antd;
          antd = new NumericAntd(instancesWithoutMissingValues.attribute(i));
          antd.value = 1;
          antd.splitPoint = lowerCore;
          newAntds.addElement(antd);
        }
      } else {
        for (int j = 0; j < m_Antds.size(); j++) {
          if (((Antd) m_Antds.elementAt(j)).att.index() == i) {
            newAntds.addElement(m_Antds.elementAt(j));
          }
        }
      }
    }
    m_Antds = newAntds;
  }
  /** Main method for testing this class. */
  public static void main(String[] options) {

    try {

      // Create numeric attributes "length" and "weight"
      Attribute length = new Attribute("length");
      Attribute weight = new Attribute("weight");

      // Create vector to hold nominal values "first", "second", "third"
      FastVector my_nominal_values = new FastVector(3);
      my_nominal_values.addElement("first");
      my_nominal_values.addElement("second");

      // Create nominal attribute "position"
      Attribute position = new Attribute("position", my_nominal_values);

      // Create vector of the above attributes
      FastVector attributes = new FastVector(3);
      attributes.addElement(length);
      attributes.addElement(weight);
      attributes.addElement(position);

      // Create the empty dataset "race" with above attributes
      Instances race = new Instances("race", attributes, 0);

      // Make position the class attribute
      race.setClassIndex(position.index());

      // Create empty instance with three attribute values
      BinarySparseInstance inst = new BinarySparseInstance(3);

      // Set instance's values for the attributes "length", "weight", and "position"
      inst.setValue(length, (float) 5.3);
      inst.setValue(weight, 300);
      inst.setValue(position, "first");

      // Set instance's dataset to be the dataset "race"
      inst.setDataset(race);

      // Print the instance
      System.out.println("The instance: " + inst);

      // Print the first attribute
      System.out.println("First attribute: " + inst.attribute(0));

      // Print the class attribute
      System.out.println("Class attribute: " + inst.classAttribute());

      // Print the class index
      System.out.println("Class index: " + inst.classIndex());

      // Say if class is missing
      System.out.println("Class is missing: " + inst.classIsMissing());

      // Print the instance's class value in internal format
      System.out.println("Class value (internal format): " + inst.classValue());

      // Print a shallow copy of this instance
      SparseInstance copy = (SparseInstance) inst.copy();
      System.out.println("Shallow copy: " + copy);

      // Set dataset for shallow copy
      copy.setDataset(inst.dataset());
      System.out.println("Shallow copy with dataset set: " + copy);

      // Print out all values in internal format
      System.out.print("All stored values in internal format: ");
      for (int i = 0; i < inst.numValues(); i++) {
        if (i > 0) {
          System.out.print(",");
        }
        System.out.print(inst.valueSparse(i));
      }
      System.out.println();

      // Set all values to zero
      System.out.print("All values set to zero: ");
      while (inst.numValues() > 0) {
        inst.setValueSparse(0, 0);
      }
      for (int i = 0; i < inst.numValues(); i++) {
        if (i > 0) {
          System.out.print(",");
        }
        System.out.print(inst.valueSparse(i));
      }
      System.out.println();

      // Set all values to one
      System.out.print("All values set to one: ");
      for (int i = 0; i < inst.numAttributes(); i++) {
        inst.setValue(i, 1);
      }
      for (int i = 0; i < inst.numValues(); i++) {
        if (i > 0) {
          System.out.print(",");
        }
        System.out.print(inst.valueSparse(i));
      }
      System.out.println();

      // Unset dataset for copy, delete first attribute, and insert it again
      copy.setDataset(null);
      copy.deleteAttributeAt(0);
      copy.insertAttributeAt(0);
      copy.setDataset(inst.dataset());
      System.out.println("Copy with first attribute deleted and inserted: " + copy);

      // Same for second attribute
      copy.setDataset(null);
      copy.deleteAttributeAt(1);
      copy.insertAttributeAt(1);
      copy.setDataset(inst.dataset());
      System.out.println("Copy with second attribute deleted and inserted: " + copy);

      // Same for last attribute
      copy.setDataset(null);
      copy.deleteAttributeAt(2);
      copy.insertAttributeAt(2);
      copy.setDataset(inst.dataset());
      System.out.println("Copy with third attribute deleted and inserted: " + copy);

      // Enumerate attributes (leaving out the class attribute)
      System.out.println("Enumerating attributes (leaving out class):");
      Enumeration enu = inst.enumerateAttributes();
      while (enu.hasMoreElements()) {
        Attribute att = (Attribute) enu.nextElement();
        System.out.println(att);
      }

      // Headers are equivalent?
      System.out.println("Header of original and copy equivalent: " + inst.equalHeaders(copy));

      // Test for missing values
      System.out.println("Length of copy missing: " + copy.isMissing(length));
      System.out.println("Weight of copy missing: " + copy.isMissing(weight.index()));
      System.out.println("Length of copy missing: " + Instance.isMissingValue(copy.value(length)));
      System.out.println("Missing value coded as: " + Instance.missingValue());

      // Prints number of attributes and classes
      System.out.println("Number of attributes: " + copy.numAttributes());
      System.out.println("Number of classes: " + copy.numClasses());

      // Replace missing values
      float[] meansAndModes = {2, 3, 0};
      copy.replaceMissingValues(meansAndModes);
      System.out.println("Copy with missing value replaced: " + copy);

      // Setting and getting values and weights
      copy.setClassMissing();
      System.out.println("Copy with missing class: " + copy);
      copy.setClassValue(0);
      System.out.println("Copy with class value set to first value: " + copy);
      copy.setClassValue("second");
      System.out.println("Copy with class value set to \"second\": " + copy);
      copy.setMissing(1);
      System.out.println("Copy with second attribute set to be missing: " + copy);
      copy.setMissing(length);
      System.out.println("Copy with length set to be missing: " + copy);
      copy.setValue(0, 0);
      System.out.println("Copy with first attribute set to 0: " + copy);
      copy.setValue(weight, 1);
      System.out.println("Copy with weight attribute set to 1: " + copy);
      copy.setValue(position, "second");
      System.out.println("Copy with position set to \"second\": " + copy);
      copy.setValue(2, "first");
      System.out.println("Copy with last attribute set to \"first\": " + copy);
      System.out.println("Current weight of instance copy: " + copy.weight());
      copy.setWeight(2);
      System.out.println("Current weight of instance copy (set to 2): " + copy.weight());
      System.out.println("Last value of copy: " + copy.toString(2));
      System.out.println("Value of position for copy: " + copy.toString(position));
      System.out.println("Last value of copy (internal format): " + copy.value(2));
      System.out.println("Value of position for copy (internal format): " + copy.value(position));
    } catch (Exception e) {
      e.printStackTrace();
    }
  }