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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
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* Copyright (C) 1999 University of Waikato, Hamilton, New Zealand
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import java.io.Serializable;
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import java.util.Enumeration;
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* Class for handling an instance. All values (numeric, date, nominal, string
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* or relational) are internally stored as floating-point numbers. If an
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* attribute is nominal (or a string or relational), the stored value is the
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* index of the corresponding nominal (or string or relational) value in the
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* attribute's definition. We have chosen this approach in favor of a more
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* elegant object-oriented approach because it is much faster. <p>
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* Typical usage (code from the main() method of this class): <p>
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* // Create empty instance with three attribute values <br>
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* Instance inst = new Instance(3); <br><br>
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* // Set instance's values for the attributes "length", "weight", and "position"<br>
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* inst.setValue(length, 5.3); <br>
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* inst.setValue(weight, 300); <br>
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* inst.setValue(position, "first"); <br><br>
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* // Set instance's dataset to be the dataset "race" <br>
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* inst.setDataset(race); <br><br>
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* // Print the instance <br>
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* System.out.println("The instance: " + inst); <br>
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* All methods that change an instance are safe, ie. a change of an
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* instance does not affect any other instances. All methods that
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* change an instance's attribute values clone the attribute value
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* vector before it is changed. If your application heavily modifies
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* instance values, it may be faster to create a new instance from scratch.
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* @author Eibe Frank (eibe@cs.waikato.ac.nz)
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* @version $Revision: 1.25 $
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implements Copyable, Serializable {
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/** for serialization */
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static final long serialVersionUID = 1482635194499365122L;
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/** Constant representing a missing value. */
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protected static final double MISSING_VALUE = Double.NaN;
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* The dataset the instance has access to. Null if the instance
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* doesn't have access to any dataset. Only if an instance has
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* access to a dataset, it knows about the actual attribute types.
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protected /*@spec_public@*/ Instances m_Dataset;
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/** The instance's attribute values. */
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protected /*@spec_public non_null@*/ double[] m_AttValues;
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/** The instance's weight. */
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protected double m_Weight;
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* Constructor that copies the attribute values and the weight from
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* the given instance. Reference to the dataset is set to null.
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* (ie. the instance doesn't have access to information about the
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* @param instance the instance from which the attribute
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* values and the weight are to be copied
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//@ ensures m_Dataset == null;
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public Instance(/*@non_null@*/ Instance instance) {
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m_AttValues = instance.m_AttValues;
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m_Weight = instance.m_Weight;
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* Constructor that inititalizes instance variable with given
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* values. Reference to the dataset is set to null. (ie. the instance
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* doesn't have access to information about the attribute types)
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* @param weight the instance's weight
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* @param attValues a vector of attribute values
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//@ ensures m_Dataset == null;
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public Instance(double weight, /*@non_null@*/ double[]attValues){
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m_AttValues = attValues;
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* Constructor of an instance that sets weight to one, all values to
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* be missing, and the reference to the dataset to null. (ie. the instance
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* doesn't have access to information about the attribute types)
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* @param numAttributes the size of the instance
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//@ requires numAttributes > 0; // Or maybe == 0 is okay too?
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//@ ensures m_Dataset == null;
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public Instance(int numAttributes) {
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m_AttValues = new double[numAttributes];
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for (int i = 0; i < m_AttValues.length; i++) {
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m_AttValues[i] = MISSING_VALUE;
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* Returns the attribute with the given index.
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* @param index the attribute's index
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* @return the attribute at the given position
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* @throws UnassignedDatasetException if instance doesn't have access to a
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//@ requires m_Dataset != null;
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public /*@pure@*/ Attribute attribute(int index) {
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if (m_Dataset == null) {
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throw new UnassignedDatasetException("Instance doesn't have access to a dataset!");
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return m_Dataset.attribute(index);
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* Returns the attribute with the given index. Does the same
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* thing as attribute().
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* @param indexOfIndex the index of the attribute's index
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* @return the attribute at the given position
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* @throws UnassignedDatasetException if instance doesn't have access to a
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//@ requires m_Dataset != null;
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public /*@pure@*/ Attribute attributeSparse(int indexOfIndex) {
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if (m_Dataset == null) {
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throw new UnassignedDatasetException("Instance doesn't have access to a dataset!");
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return m_Dataset.attribute(indexOfIndex);
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* Returns class attribute.
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* @return the class attribute
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* @throws UnassignedDatasetException if the class is not set or the
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* instance doesn't have access to a dataset
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//@ requires m_Dataset != null;
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public /*@pure@*/ Attribute classAttribute() {
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if (m_Dataset == null) {
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throw new UnassignedDatasetException("Instance doesn't have access to a dataset!");
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return m_Dataset.classAttribute();
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* Returns the class attribute's index.
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* @return the class index as an integer
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* @throws UnassignedDatasetException if instance doesn't have access to a dataset
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//@ requires m_Dataset != null;
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//@ ensures \result == m_Dataset.classIndex();
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public /*@pure@*/ int classIndex() {
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if (m_Dataset == null) {
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throw new UnassignedDatasetException("Instance doesn't have access to a dataset!");
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return m_Dataset.classIndex();
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* Tests if an instance's class is missing.
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* @return true if the instance's class is missing
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* @throws UnassignedClassException if the class is not set or the instance doesn't
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* have access to a dataset
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//@ requires classIndex() >= 0;
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public /*@pure@*/ boolean classIsMissing() {
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if (classIndex() < 0) {
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throw new UnassignedClassException("Class is not set!");
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return isMissing(classIndex());
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* Returns an instance's class value in internal format. (ie. as a
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* floating-point number)
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* @return the corresponding value as a double (If the
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* corresponding attribute is nominal (or a string) then it returns the
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* value's index as a double).
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* @throws UnassignedClassException if the class is not set or the instance doesn't
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* have access to a dataset
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//@ requires classIndex() >= 0;
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public /*@pure@*/ double classValue() {
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if (classIndex() < 0) {
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throw new UnassignedClassException("Class is not set!");
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return value(classIndex());
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* Produces a shallow copy of this instance. The copy has
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* access to the same dataset. (if you want to make a copy
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* that doesn't have access to the dataset, use
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* <code>new Instance(instance)</code>
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* @return the shallow copy
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//@ also ensures \result != null;
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//@ also ensures \result instanceof Instance;
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//@ also ensures ((Instance)\result).m_Dataset == m_Dataset;
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public /*@pure@*/ Object copy() {
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Instance result = new Instance(this);
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result.m_Dataset = m_Dataset;
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* Returns the dataset this instance has access to. (ie. obtains
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* information about attribute types from) Null if the instance
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* doesn't have access to a dataset.
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* @return the dataset the instance has accesss to
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//@ ensures \result == m_Dataset;
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public /*@pure@*/ Instances dataset() {
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* Deletes an attribute at the given position (0 to
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* numAttributes() - 1). Only succeeds if the instance does not
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* have access to any dataset because otherwise inconsistencies
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* could be introduced.
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* @param position the attribute's position
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* @throws RuntimeException if the instance has access to a
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//@ requires m_Dataset != null;
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public void deleteAttributeAt(int position) {
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if (m_Dataset != null) {
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throw new RuntimeException("Instance has access to a dataset!");
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forceDeleteAttributeAt(position);
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* Returns an enumeration of all the attributes.
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* @return enumeration of all the attributes
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* @throws UnassignedDatasetException if the instance doesn't
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* have access to a dataset
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//@ requires m_Dataset != null;
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public /*@pure@*/ Enumeration enumerateAttributes() {
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if (m_Dataset == null) {
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throw new UnassignedDatasetException("Instance doesn't have access to a dataset!");
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return m_Dataset.enumerateAttributes();
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* Tests if the headers of two instances are equivalent.
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* @param inst another instance
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* @return true if the header of the given instance is
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* equivalent to this instance's header
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* @throws UnassignedDatasetException if instance doesn't have access to any
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//@ requires m_Dataset != null;
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public /*@pure@*/ boolean equalHeaders(Instance inst) {
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if (m_Dataset == null) {
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throw new UnassignedDatasetException("Instance doesn't have access to a dataset!");
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return m_Dataset.equalHeaders(inst.m_Dataset);
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* Tests whether an instance has a missing value. Skips the class attribute if set.
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* @return true if instance has a missing value.
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* @throws UnassignedDatasetException if instance doesn't have access to any
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//@ requires m_Dataset != null;
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public /*@pure@*/ boolean hasMissingValue() {
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if (m_Dataset == null) {
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throw new UnassignedDatasetException("Instance doesn't have access to a dataset!");
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for (int i = 0; i < numAttributes(); i++) {
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if (i != classIndex()) {
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* Returns the index of the attribute stored at the given position.
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* Just returns the given value.
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* @param position the position
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* @return the index of the attribute stored at the given position
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public /*@pure@*/ int index(int position) {
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* Inserts an attribute at the given position (0 to
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* numAttributes()). Only succeeds if the instance does not
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* have access to any dataset because otherwise inconsistencies
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* could be introduced.
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* @param position the attribute's position
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* @throws RuntimeException if the instance has accesss to a
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* @throws IllegalArgumentException if the position is out of range
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//@ requires m_Dataset == null;
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//@ requires 0 <= position && position <= numAttributes();
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public void insertAttributeAt(int position) {
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if (m_Dataset != null) {
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throw new RuntimeException("Instance has accesss to a dataset!");
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if ((position < 0) ||
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(position > numAttributes())) {
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throw new IllegalArgumentException("Can't insert attribute: index out "+
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forceInsertAttributeAt(position);
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* Tests if a specific value is "missing".
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* @param attIndex the attribute's index
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* @return true if the value is "missing"
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public /*@pure@*/ boolean isMissing(int attIndex) {
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if (Double.isNaN(m_AttValues[attIndex])) {
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* Tests if a specific value is "missing". Does
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* the same thing as isMissing() if applied to an Instance.
405
* @param indexOfIndex the index of the attribute's index
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* @return true if the value is "missing"
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public /*@pure@*/ boolean isMissingSparse(int indexOfIndex) {
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if (Double.isNaN(m_AttValues[indexOfIndex])) {
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* Tests if a specific value is "missing".
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* The given attribute has to belong to a dataset.
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* @param att the attribute
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* @return true if the value is "missing"
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public /*@pure@*/ boolean isMissing(Attribute att) {
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return isMissing(att.index());
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* Tests if the given value codes "missing".
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* @param val the value to be tested
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* @return true if val codes "missing"
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public static /*@pure@*/ boolean isMissingValue(double val) {
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return Double.isNaN(val);
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* Merges this instance with the given instance and returns
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* the result. Dataset is set to null.
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* @param inst the instance to be merged with this one
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* @return the merged instances
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public Instance mergeInstance(Instance inst) {
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double [] newVals = new double[numAttributes() + inst.numAttributes()];
450
for (int j = 0; j < numAttributes(); j++, m++) {
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newVals[m] = value(j);
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for (int j = 0; j < inst.numAttributes(); j++, m++) {
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newVals[m] = inst.value(j);
456
return new Instance(1.0, newVals);
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* Returns the double that codes "missing".
462
* @return the double that codes "missing"
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public /*@pure@*/ static double missingValue() {
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return MISSING_VALUE;
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* Returns the number of attributes.
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* @return the number of attributes as an integer
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//@ ensures \result == m_AttValues.length;
475
public /*@pure@*/ int numAttributes() {
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return m_AttValues.length;
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* Returns the number of class labels.
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* @return the number of class labels as an integer if the
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* class attribute is nominal, 1 otherwise.
485
* @throws UnassignedDatasetException if instance doesn't have access to any
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//@ requires m_Dataset != null;
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public /*@pure@*/ int numClasses() {
491
if (m_Dataset == null) {
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throw new UnassignedDatasetException("Instance doesn't have access to a dataset!");
494
return m_Dataset.numClasses();
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* Returns the number of values present. Always the same as numAttributes().
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* @return the number of values
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//@ ensures \result == m_AttValues.length;
503
public /*@pure@*/ int numValues() {
505
return m_AttValues.length;
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* Replaces all missing values in the instance with the
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* values contained in the given array. A deep copy of
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* the vector of attribute values is performed before the
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* values are replaced.
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* @param array containing the means and modes
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* @throws IllegalArgumentException if numbers of attributes are unequal
517
public void replaceMissingValues(double[] array) {
519
if ((array == null) ||
520
(array.length != m_AttValues.length)) {
521
throw new IllegalArgumentException("Unequal number of attributes!");
523
freshAttributeVector();
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for (int i = 0; i < m_AttValues.length; i++) {
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m_AttValues[i] = array[i];
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* Sets the class value of an instance to be "missing". A deep copy of
533
* the vector of attribute values is performed before the
534
* value is set to be missing.
536
* @throws UnassignedClassException if the class is not set
537
* @throws UnassignedDatasetException if the instance doesn't
538
* have access to a dataset
540
//@ requires classIndex() >= 0;
541
public void setClassMissing() {
543
if (classIndex() < 0) {
544
throw new UnassignedClassException("Class is not set!");
546
setMissing(classIndex());
550
* Sets the class value of an instance to the given value (internal
551
* floating-point format). A deep copy of the vector of attribute
552
* values is performed before the value is set.
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* @param value the new attribute value (If the corresponding
555
* attribute is nominal (or a string) then this is the new value's
556
* index as a double).
557
* @throws UnassignedClassException if the class is not set
558
* @throws UnaddignedDatasetException if the instance doesn't
559
* have access to a dataset
561
//@ requires classIndex() >= 0;
562
public void setClassValue(double value) {
564
if (classIndex() < 0) {
565
throw new UnassignedClassException("Class is not set!");
567
setValue(classIndex(), value);
571
* Sets the class value of an instance to the given value. A deep
572
* copy of the vector of attribute values is performed before the
575
* @param value the new class value (If the class
576
* is a string attribute and the value can't be found,
577
* the value is added to the attribute).
578
* @throws UnassignedClassException if the class is not set
579
* @throws UnassignedDatasetException if the dataset is not set
580
* @throws IllegalArgumentException if the attribute is not
581
* nominal or a string, or the value couldn't be found for a nominal
584
//@ requires classIndex() >= 0;
585
public final void setClassValue(String value) {
587
if (classIndex() < 0) {
588
throw new UnassignedClassException("Class is not set!");
590
setValue(classIndex(), value);
594
* Sets the reference to the dataset. Does not check if the instance
595
* is compatible with the dataset. Note: the dataset does not know
596
* about this instance. If the structure of the dataset's header
597
* gets changed, this instance will not be adjusted automatically.
599
* @param instances the reference to the dataset
601
public final void setDataset(Instances instances) {
603
m_Dataset = instances;
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* Sets a specific value to be "missing". Performs a deep copy
608
* of the vector of attribute values before the value is set to
611
* @param attIndex the attribute's index
613
public final void setMissing(int attIndex) {
615
setValue(attIndex, MISSING_VALUE);
619
* Sets a specific value to be "missing". Performs a deep copy
620
* of the vector of attribute values before the value is set to
621
* be missing. The given attribute has to belong to a dataset.
623
* @param att the attribute
625
public final void setMissing(Attribute att) {
627
setMissing(att.index());
631
* Sets a specific value in the instance to the given value
632
* (internal floating-point format). Performs a deep copy
633
* of the vector of attribute values before the value is set.
635
* @param attIndex the attribute's index
636
* @param value the new attribute value (If the corresponding
637
* attribute is nominal (or a string) then this is the new value's
638
* index as a double).
640
public void setValue(int attIndex, double value) {
642
freshAttributeVector();
643
m_AttValues[attIndex] = value;
647
* Sets a specific value in the instance to the given value
648
* (internal floating-point format). Performs a deep copy
649
* of the vector of attribute values before the value is set.
650
* Does exactly the same thing as setValue().
652
* @param indexOfIndex the index of the attribute's index
653
* @param value the new attribute value (If the corresponding
654
* attribute is nominal (or a string) then this is the new value's
655
* index as a double).
657
public void setValueSparse(int indexOfIndex, double value) {
659
freshAttributeVector();
660
m_AttValues[indexOfIndex] = value;
664
* Sets a value of a nominal or string attribute to the given
665
* value. Performs a deep copy of the vector of attribute values
666
* before the value is set.
668
* @param attIndex the attribute's index
669
* @param value the new attribute value (If the attribute
670
* is a string attribute and the value can't be found,
671
* the value is added to the attribute).
672
* @throws UnassignedDatasetException if the dataset is not set
673
* @throws IllegalArgumentException if the selected
674
* attribute is not nominal or a string, or the supplied value couldn't
675
* be found for a nominal attribute
677
//@ requires m_Dataset != null;
678
public final void setValue(int attIndex, String value) {
682
if (m_Dataset == null) {
683
throw new UnassignedDatasetException("Instance doesn't have access to a dataset!");
685
if (!attribute(attIndex).isNominal() &&
686
!attribute(attIndex).isString()) {
687
throw new IllegalArgumentException("Attribute neither nominal nor string!");
689
valIndex = attribute(attIndex).indexOfValue(value);
690
if (valIndex == -1) {
691
if (attribute(attIndex).isNominal()) {
692
throw new IllegalArgumentException("Value not defined for given nominal attribute!");
694
attribute(attIndex).forceAddValue(value);
695
valIndex = attribute(attIndex).indexOfValue(value);
698
setValue(attIndex, (double)valIndex);
702
* Sets a specific value in the instance to the given value
703
* (internal floating-point format). Performs a deep copy of the
704
* vector of attribute values before the value is set, so if you are
705
* planning on calling setValue many times it may be faster to
706
* create a new instance using toDoubleArray. The given attribute
707
* has to belong to a dataset.
709
* @param att the attribute
710
* @param value the new attribute value (If the corresponding
711
* attribute is nominal (or a string) then this is the new value's
712
* index as a double).
714
public final void setValue(Attribute att, double value) {
716
setValue(att.index(), value);
720
* Sets a value of an nominal or string attribute to the given
721
* value. Performs a deep copy of the vector of attribute values
722
* before the value is set, so if you are planning on calling setValue many
723
* times it may be faster to create a new instance using toDoubleArray.
724
* The given attribute has to belong to a dataset.
726
* @param att the attribute
727
* @param value the new attribute value (If the attribute
728
* is a string attribute and the value can't be found,
729
* the value is added to the attribute).
730
* @throws IllegalArgumentException if the the attribute is not
731
* nominal or a string, or the value couldn't be found for a nominal
734
public final void setValue(Attribute att, String value) {
736
if (!att.isNominal() &&
738
throw new IllegalArgumentException("Attribute neither nominal nor string!");
740
int valIndex = att.indexOfValue(value);
741
if (valIndex == -1) {
742
if (att.isNominal()) {
743
throw new IllegalArgumentException("Value not defined for given nominal attribute!");
745
att.forceAddValue(value);
746
valIndex = att.indexOfValue(value);
749
setValue(att.index(), (double)valIndex);
753
* Sets the weight of an instance.
755
* @param weight the weight
757
public final void setWeight(double weight) {
763
* Returns the relational value of a relational attribute.
765
* @param attIndex the attribute's index
766
* @return the corresponding relation as an Instances object
767
* @throws IllegalArgumentException if the attribute is not a
768
* relation-valued attribute
769
* @throws UnassignedDatasetException if the instance doesn't belong
772
//@ requires m_Dataset != null;
773
public final /*@pure@*/ Instances relationalValue(int attIndex) {
775
if (m_Dataset == null) {
776
throw new UnassignedDatasetException("Instance doesn't have access to a dataset!");
778
return relationalValue(m_Dataset.attribute(attIndex));
783
* Returns the relational value of a relational attribute.
785
* @param att the attribute
786
* @return the corresponding relation as an Instances object
787
* @throws IllegalArgumentException if the attribute is not a
788
* relation-valued attribute
789
* @throws UnassignedDatasetException if the instance doesn't belong
792
public final /*@pure@*/ Instances relationalValue(Attribute att) {
794
int attIndex = att.index();
795
if (att.isRelationValued()) {
796
return att.relation((int) value(attIndex));
798
throw new IllegalArgumentException("Attribute isn't relation-valued!");
803
* Returns the value of a nominal, string, date, or relational attribute
804
* for the instance as a string.
806
* @param attIndex the attribute's index
807
* @return the value as a string
808
* @throws IllegalArgumentException if the attribute is not a nominal,
809
* string, date, or relation-valued attribute.
810
* @throws UnassignedDatasetException if the instance doesn't belong
813
//@ requires m_Dataset != null;
814
public final /*@pure@*/ String stringValue(int attIndex) {
816
if (m_Dataset == null) {
817
throw new UnassignedDatasetException("Instance doesn't have access to a dataset!");
819
return stringValue(m_Dataset.attribute(attIndex));
824
* Returns the value of a nominal, string, date, or relational attribute
825
* for the instance as a string.
827
* @param att the attribute
828
* @return the value as a string
829
* @throws IllegalArgumentException if the attribute is not a nominal,
830
* string, date, or relation-valued attribute.
831
* @throws UnassignedDatasetException if the instance doesn't belong
834
public final /*@pure@*/ String stringValue(Attribute att) {
836
int attIndex = att.index();
837
switch (att.type()) {
838
case Attribute.NOMINAL:
839
case Attribute.STRING:
840
return att.value((int) value(attIndex));
842
return att.formatDate(value(attIndex));
843
case Attribute.RELATIONAL:
844
return att.relation((int) value(attIndex)).stringWithoutHeader();
846
throw new IllegalArgumentException("Attribute isn't nominal, string or date!");
851
* Returns the values of each attribute as an array of doubles.
853
* @return an array containing all the instance attribute values
855
public double[] toDoubleArray() {
857
double[] newValues = new double[m_AttValues.length];
858
System.arraycopy(m_AttValues, 0, newValues, 0,
864
* Returns the description of one instance. If the instance
865
* doesn't have access to a dataset, it returns the internal
866
* floating-point values. Quotes string
867
* values that contain whitespace characters.
869
* @return the instance's description as a string
871
public String toString() {
873
StringBuffer text = new StringBuffer();
875
for (int i = 0; i < m_AttValues.length; i++) {
876
if (i > 0) text.append(",");
877
text.append(toString(i));
880
return text.toString();
884
* Returns the description of one value of the instance as a
885
* string. If the instance doesn't have access to a dataset, it
886
* returns the internal floating-point value. Quotes string
887
* values that contain whitespace characters, or if they
888
* are a question mark.
890
* @param attIndex the attribute's index
891
* @return the value's description as a string
893
public final /*@pure@*/ String toString(int attIndex) {
895
StringBuffer text = new StringBuffer();
897
if (isMissing(attIndex)) {
900
if (m_Dataset == null) {
901
text.append(Utils.doubleToString(m_AttValues[attIndex],6));
903
switch (m_Dataset.attribute(attIndex).type()) {
904
case Attribute.NOMINAL:
905
case Attribute.STRING:
907
case Attribute.RELATIONAL:
908
text.append(Utils.quote(stringValue(attIndex)));
910
case Attribute.NUMERIC:
911
text.append(Utils.doubleToString(value(attIndex),6));
914
throw new IllegalStateException("Unknown attribute type");
918
return text.toString();
922
* Returns the description of one value of the instance as a
923
* string. If the instance doesn't have access to a dataset it
924
* returns the internal floating-point value. Quotes string
925
* values that contain whitespace characters, or if they
926
* are a question mark.
927
* The given attribute has to belong to a dataset.
929
* @param att the attribute
930
* @return the value's description as a string
932
public final String toString(Attribute att) {
934
return toString(att.index());
938
* Returns an instance's attribute value in internal format.
940
* @param attIndex the attribute's index
941
* @return the specified value as a double (If the corresponding
942
* attribute is nominal (or a string) then it returns the value's index as a
945
public /*@pure@*/ double value(int attIndex) {
947
return m_AttValues[attIndex];
951
* Returns an instance's attribute value in internal format.
952
* Does exactly the same thing as value() if applied to an Instance.
954
* @param indexOfIndex the index of the attribute's index
955
* @return the specified value as a double (If the corresponding
956
* attribute is nominal (or a string) then it returns the value's index as a
959
public /*@pure@*/ double valueSparse(int indexOfIndex) {
961
return m_AttValues[indexOfIndex];
965
* Returns an instance's attribute value in internal format.
966
* The given attribute has to belong to a dataset.
968
* @param att the attribute
969
* @return the specified value as a double (If the corresponding
970
* attribute is nominal (or a string) then it returns the value's index as a
973
public /*@pure@*/ double value(Attribute att) {
975
return value(att.index());
979
* Returns the instance's weight.
981
* @return the instance's weight as a double
983
public final /*@pure@*/ double weight() {
989
* Deletes an attribute at the given position (0 to
990
* numAttributes() - 1).
992
* @param position the attribute's position
994
void forceDeleteAttributeAt(int position) {
996
double[] newValues = new double[m_AttValues.length - 1];
998
System.arraycopy(m_AttValues, 0, newValues, 0, position);
999
if (position < m_AttValues.length - 1) {
1000
System.arraycopy(m_AttValues, position + 1,
1001
newValues, position,
1002
m_AttValues.length - (position + 1));
1004
m_AttValues = newValues;
1008
* Inserts an attribute at the given position
1009
* (0 to numAttributes()) and sets its value to be missing.
1011
* @param position the attribute's position
1013
void forceInsertAttributeAt(int position) {
1015
double[] newValues = new double[m_AttValues.length + 1];
1017
System.arraycopy(m_AttValues, 0, newValues, 0, position);
1018
newValues[position] = MISSING_VALUE;
1019
System.arraycopy(m_AttValues, position, newValues,
1020
position + 1, m_AttValues.length - position);
1021
m_AttValues = newValues;
1025
* Private constructor for subclasses. Does nothing.
1027
protected Instance() {
1031
* Clones the attribute vector of the instance and
1032
* overwrites it with the clone.
1034
private void freshAttributeVector() {
1036
m_AttValues = toDoubleArray();
1040
* Main method for testing this class.
1042
* @param options the commandline options - ignored
1044
//@ requires options != null;
1045
public static void main(String[] options) {
1049
// Create numeric attributes "length" and "weight"
1050
Attribute length = new Attribute("length");
1051
Attribute weight = new Attribute("weight");
1053
// Create vector to hold nominal values "first", "second", "third"
1054
FastVector my_nominal_values = new FastVector(3);
1055
my_nominal_values.addElement("first");
1056
my_nominal_values.addElement("second");
1057
my_nominal_values.addElement("third");
1059
// Create nominal attribute "position"
1060
Attribute position = new Attribute("position", my_nominal_values);
1062
// Create vector of the above attributes
1063
FastVector attributes = new FastVector(3);
1064
attributes.addElement(length);
1065
attributes.addElement(weight);
1066
attributes.addElement(position);
1068
// Create the empty dataset "race" with above attributes
1069
Instances race = new Instances("race", attributes, 0);
1071
// Make position the class attribute
1072
race.setClassIndex(position.index());
1074
// Create empty instance with three attribute values
1075
Instance inst = new Instance(3);
1077
// Set instance's values for the attributes "length", "weight", and "position"
1078
inst.setValue(length, 5.3);
1079
inst.setValue(weight, 300);
1080
inst.setValue(position, "first");
1082
// Set instance's dataset to be the dataset "race"
1083
inst.setDataset(race);
1085
// Print the instance
1086
System.out.println("The instance: " + inst);
1088
// Print the first attribute
1089
System.out.println("First attribute: " + inst.attribute(0));
1091
// Print the class attribute
1092
System.out.println("Class attribute: " + inst.classAttribute());
1094
// Print the class index
1095
System.out.println("Class index: " + inst.classIndex());
1097
// Say if class is missing
1098
System.out.println("Class is missing: " + inst.classIsMissing());
1100
// Print the instance's class value in internal format
1101
System.out.println("Class value (internal format): " + inst.classValue());
1103
// Print a shallow copy of this instance
1104
Instance copy = (Instance) inst.copy();
1105
System.out.println("Shallow copy: " + copy);
1107
// Set dataset for shallow copy
1108
copy.setDataset(inst.dataset());
1109
System.out.println("Shallow copy with dataset set: " + copy);
1111
// Unset dataset for copy, delete first attribute, and insert it again
1112
copy.setDataset(null);
1113
copy.deleteAttributeAt(0);
1114
copy.insertAttributeAt(0);
1115
copy.setDataset(inst.dataset());
1116
System.out.println("Copy with first attribute deleted and inserted: " + copy);
1118
// Enumerate attributes (leaving out the class attribute)
1119
System.out.println("Enumerating attributes (leaving out class):");
1120
Enumeration enu = inst.enumerateAttributes();
1121
while (enu.hasMoreElements()) {
1122
Attribute att = (Attribute) enu.nextElement();
1123
System.out.println(att);
1126
// Headers are equivalent?
1127
System.out.println("Header of original and copy equivalent: " +
1128
inst.equalHeaders(copy));
1130
// Test for missing values
1131
System.out.println("Length of copy missing: " + copy.isMissing(length));
1132
System.out.println("Weight of copy missing: " + copy.isMissing(weight.index()));
1133
System.out.println("Length of copy missing: " +
1134
Instance.isMissingValue(copy.value(length)));
1135
System.out.println("Missing value coded as: " + Instance.missingValue());
1137
// Prints number of attributes and classes
1138
System.out.println("Number of attributes: " + copy.numAttributes());
1139
System.out.println("Number of classes: " + copy.numClasses());
1141
// Replace missing values
1142
double[] meansAndModes = {2, 3, 0};
1143
copy.replaceMissingValues(meansAndModes);
1144
System.out.println("Copy with missing value replaced: " + copy);
1146
// Setting and getting values and weights
1147
copy.setClassMissing();
1148
System.out.println("Copy with missing class: " + copy);
1149
copy.setClassValue(0);
1150
System.out.println("Copy with class value set to first value: " + copy);
1151
copy.setClassValue("third");
1152
System.out.println("Copy with class value set to \"third\": " + copy);
1154
System.out.println("Copy with second attribute set to be missing: " + copy);
1155
copy.setMissing(length);
1156
System.out.println("Copy with length set to be missing: " + copy);
1157
copy.setValue(0, 0);
1158
System.out.println("Copy with first attribute set to 0: " + copy);
1159
copy.setValue(weight, 1);
1160
System.out.println("Copy with weight attribute set to 1: " + copy);
1161
copy.setValue(position, "second");
1162
System.out.println("Copy with position set to \"second\": " + copy);
1163
copy.setValue(2, "first");
1164
System.out.println("Copy with last attribute set to \"first\": " + copy);
1165
System.out.println("Current weight of instance copy: " + copy.weight());
1167
System.out.println("Current weight of instance copy (set to 2): " + copy.weight());
1168
System.out.println("Last value of copy: " + copy.toString(2));
1169
System.out.println("Value of position for copy: " + copy.toString(position));
1170
System.out.println("Last value of copy (internal format): " + copy.value(2));
1171
System.out.println("Value of position for copy (internal format): " +
1172
copy.value(position));
1173
} catch (Exception e) {
1174
e.printStackTrace();
added
removed
weka/core/Instance.java
