Java Code Examples for weka.core.DenseInstance#setDataset()

/**
 * Processes the given data.
 *
 * @param instances   the data to process
 * @return            the modified data
 * @throws Exception  in case the processing goes wrong
 */
public Instances process(Instances instances) throws Exception {

  // Generate the output and return it
  Instances result = new Instances(getOutputFormat(), instances.numInstances());
  for (int i = 0; i < instances.numInstances(); i++) {
    Instance inst = instances.instance(i);
    double[] newData = new double[instances.numAttributes()];
    for (int j = 0; j < instances.numAttributes(); j++) {
      if (m_AttToBeModified[j] && !inst.isMissing(j)) {
        newData[j] = m_NewValues[j][(int)inst.value(j)];
      } else {
        newData[j] = inst.value(j);
      }
    }
    DenseInstance instNew = new DenseInstance(1.0, newData);
    instNew.setDataset(result);
    
    // copy possible strings, relational values...
    copyValues(instNew, false, inst.dataset(), getOutputFormat());

    // Add instance to output
    result.add(instNew);
  }
  return result;
}
 

public void cifar10InstancesAttributesTest() {
    ArrayList<Attribute> atts = new ArrayList<>();
    for (int i = 0; i < 32 * 32 * 3 + 1; i++) {
        atts.add(new Attribute("blub" + i));
    }
    Instances instances = new Instances("test", atts, 1);
    DenseInstance inst = new DenseInstance(atts.size());
    for (int i = 0; i < inst.numAttributes(); i++) {
        inst.setValue(i, 1d);
    }
    inst.setDataset(instances);
    instances.add(inst);

    INDArray result = DataSetUtils.cifar10InstanceToMatrix(inst);
    Assert.assertArrayEquals(new long[]{32, 32, 3}, result.shape());
}
 

public static Instances datasetToWekaInstances(final ILabeledDataset<? extends ILabeledInstance> dataset) throws UnsupportedAttributeTypeException {
	Instances wekaInstances = createDatasetFromSchema(dataset.getInstanceSchema());
	int expectedAttributes = dataset.getInstanceSchema().getNumAttributes();
	for (ILabeledInstance inst : dataset) {
		if (inst.getNumAttributes() != expectedAttributes) {
			throw new IllegalStateException("Dataset scheme defines a number of " + expectedAttributes + " attributes, but instance has " + inst.getNumAttributes() + ". Attributes in scheme: " + dataset.getInstanceSchema().getAttributeList().stream().map(a -> "\n\t" + a.getName() + " (" + a.toString() + ")").collect(Collectors.joining()) + ". Attributes in instance: " + Arrays.stream(inst.getAttributes()).map(a -> "\n\t" + a.toString()).collect(Collectors.joining()));
		}
		double[] point = inst.getPoint();
		double[] pointWithLabel = Arrays.copyOf(point, point.length + 1);
		DenseInstance iNew = new DenseInstance(1, pointWithLabel);
		iNew.setDataset(wekaInstances);
		if (dataset.getLabelAttribute() instanceof ICategoricalAttribute) {
			iNew.setClassValue(((ICategoricalAttribute) dataset.getLabelAttribute()).getLabelOfCategory((int)inst.getLabel()));
		} else {
			iNew.setClassValue(Double.parseDouble(inst.getLabel().toString()));
		}
		wekaInstances.add(iNew); // this MUST come here AFTER having set the class value; otherwise, the class is not registered correctly in the Instances object!!
	}
	return wekaInstances;
}
 

public static Instances datasetToWekaInstances(final ILabeledDataset<? extends ILabeledInstance> dataset) throws UnsupportedAttributeTypeException {
	Instances wekaInstances = createDatasetFromSchema(dataset.getInstanceSchema());
	for (ILabeledInstance inst : dataset) {
		double[] point = inst.getPoint();
		double[] pointWithLabel = Arrays.copyOf(point, point.length + 1);
		DenseInstance iNew = new DenseInstance(1, pointWithLabel);
		iNew.setDataset(wekaInstances);
		if (dataset.getLabelAttribute() instanceof ICategoricalAttribute) {
			iNew.setClassValue(((ICategoricalAttribute) dataset.getLabelAttribute()).getLabelOfCategory((int) inst.getLabel()));
		} else {
			iNew.setClassValue((Double) inst.getLabel());
		}
		wekaInstances.add(iNew); // this MUST come here AFTER having set the class value; otherwise, the class is not registered correctly in the Instances object!!
	}
	return wekaInstances;
}
 

public static void main(String[] args) throws Exception {
    Classifier j48 = new J48();
    Instances trainingData = GenerateTestVessels.getData();
    j48.buildClassifier(trainingData);
    System.out.println(j48);



    double[] vesselUnderTest = GenerateTestVessels.getBarco(5);

    DenseInstance inst = new DenseInstance(1.0,vesselUnderTest);
    inst.setDataset(trainingData);
    inst.setClassMissing();
    System.out.println(inst);

    double result = j48.classifyInstance(inst);
    System.out.println(GenerateTestVessels.types[(int)result]);

    SerializationHelper.write(new FileOutputStream("tmp"), j48);
    J48 j48Read = (J48)SerializationHelper.read(new FileInputStream("tmp"));
}
 

/**
 * Processes the given data.
 * 
 * @param instances the data to process
 * @return the modified data
 * @throws Exception in case the processing goes wrong
 */
@Override
public Instances process(Instances instances) throws Exception {

  // Generate the output and return it
  Instances result = new Instances(getOutputFormat(),
      instances.numInstances());
  for (int i = 0; i < instances.numInstances(); i++) {
    Instance inst = instances.instance(i);
    double[] newData = new double[instances.numAttributes()];
    for (int j = 0; j < instances.numAttributes(); j++) {
      if (m_AttToBeModified[j] && !inst.isMissing(j)) {
        newData[j] = m_Indicators[j][(int) inst.value(j)];
      } else {
        newData[j] = inst.value(j);
      }
    }
    DenseInstance instNew = new DenseInstance(1.0, newData);
    instNew.setDataset(result);

    // copy possible strings, relational values...
    copyValues(instNew, false, inst.dataset(), getOutputFormat());

    // Add instance to output
    result.add(instNew);
  }
  return result;
}
 

protected Instance makeInstance() throws IOException {

    if (m_current == null) {
      return null;
    }

    double[] vals = new double[m_structure.numAttributes()];
    for (int i = 0; i < m_structure.numAttributes(); i++) {
      Object val = m_current.get(i);
      if (val.toString().equals("?")) {
        vals[i] = Utils.missingValue();
      } else if (m_structure.attribute(i).isString()) {
        vals[i] = 0;
        m_structure.attribute(i).setStringValue(Utils.unquote(val.toString()));
      } else if (m_structure.attribute(i).isDate()) {
        String format = m_structure.attribute(i).getDateFormat();
        SimpleDateFormat sdf = new SimpleDateFormat(format);
        try {
          vals[i] = sdf.parse(val.toString()).getTime();
        } catch (ParseException e) {
          throw new IOException("Unable to parse date value " + val.toString()
              + " using date format " + format + " for date attribute "
              + m_structure.attribute(i));
        }
      } else if (m_structure.attribute(i).isNumeric()) {
        try {
          Double v = Double.parseDouble(val.toString());
          vals[i] = v.doubleValue();
        } catch (NumberFormatException ex) {
          throw new IOException("Was expecting a number for attribute "
              + m_structure.attribute(i).name() + " but read " + val.toString()
              + " instead.");
        }
      } else {
        // nominal
        double index = m_structure.attribute(i).indexOfValue(
            Utils.unquote(val.toString()));
        if (index < 0) {
          throw new IOException("Read unknown nominal value " + val.toString()
              + "for attribute " + m_structure.attribute(i).name());
        }
        vals[i] = index;
      }
    }

    DenseInstance inst = new DenseInstance(1.0, vals);
    inst.setDataset(m_structure);

    return inst;
  }