public static Instances getInstances(String file) throws Exception {
DataSource datasource = new DataSource(file);
Instances data = datasource.getDataSet();
System.out.println("Class index is : " + data.classIndex());
if (data.classIndex() == -1) data.setClassIndex(data.numAttributes() - 1);
return data;
}
/**
* Method for building this classifier.
*
* @param training the training instances
* @param test the test instances
* @throws Exception if something goes wrong
*/
public void buildClassifier(Instances training, Instances test) throws Exception {
m_ClassifierBuilt = true;
m_Random = new Random(m_Seed);
m_Trainset = training;
m_Testset = test;
// set class index?
if ((m_Trainset.classIndex() == -1) || (m_Testset.classIndex() == -1)) {
m_Trainset.setClassIndex(m_Trainset.numAttributes() - 1);
m_Testset.setClassIndex(m_Trainset.numAttributes() - 1);
}
// are datasets correct?
checkData();
// any other data restrictions not met?
checkRestrictions();
// generate sets
generateSets();
// performs the restarts/iterations
build();
m_Random = null;
}
/**
* Sets the format of the input instances.
*
* @param instanceInfo an Instances object containing the input instance structure (any instances
* contained in the object are ignored - only the structure is required).
* @return true if the outputFormat may be collected immediately
* @throws UnsupportedAttributeTypeException if selected attributes are not numeric or nominal.
*/
public boolean setInputFormat(Instances instanceInfo) throws Exception {
if ((instanceInfo.classIndex() > 0) && (!getFillWithMissing())) {
throw new IllegalArgumentException(
"TimeSeriesTranslate: Need to fill in missing values "
+ "using appropriate option when class index is set.");
}
super.setInputFormat(instanceInfo);
// Create the output buffer
Instances outputFormat = new Instances(instanceInfo, 0);
for (int i = 0; i < instanceInfo.numAttributes(); i++) {
if (i != instanceInfo.classIndex()) {
if (m_SelectedCols.isInRange(i)) {
if (outputFormat.attribute(i).isNominal() || outputFormat.attribute(i).isNumeric()) {
outputFormat.renameAttribute(
i,
outputFormat.attribute(i).name()
+ (m_InstanceRange < 0 ? '-' : '+')
+ Math.abs(m_InstanceRange));
} else {
throw new UnsupportedAttributeTypeException(
"Only numeric and nominal attributes may be " + " manipulated in time series.");
}
}
}
}
outputFormat.setClassIndex(instanceInfo.classIndex());
setOutputFormat(outputFormat);
return true;
}
/**
* Builds a regression model for the given data.
*
* @param data the training data to be used for generating the linear regression function
* @throws Exception if the classifier could not be built successfully
*/
public void buildClassifier(Instances data) throws Exception {
if (!m_checksTurnedOff) {
// can classifier handle the data?
getCapabilities().testWithFail(data);
// remove instances with missing class
data = new Instances(data);
data.deleteWithMissingClass();
}
// Preprocess instances
if (!m_checksTurnedOff) {
m_TransformFilter = new NominalToBinary();
m_TransformFilter.setInputFormat(data);
data = Filter.useFilter(data, m_TransformFilter);
m_MissingFilter = new ReplaceMissingValues();
m_MissingFilter.setInputFormat(data);
data = Filter.useFilter(data, m_MissingFilter);
data.deleteWithMissingClass();
} else {
m_TransformFilter = null;
m_MissingFilter = null;
}
m_ClassIndex = data.classIndex();
m_TransformedData = data;
// Turn all attributes on for a start
m_SelectedAttributes = new boolean[data.numAttributes()];
for (int i = 0; i < data.numAttributes(); i++) {
if (i != m_ClassIndex) {
m_SelectedAttributes[i] = true;
}
}
m_Coefficients = null;
// Compute means and standard deviations
m_Means = new double[data.numAttributes()];
m_StdDevs = new double[data.numAttributes()];
for (int j = 0; j < data.numAttributes(); j++) {
if (j != data.classIndex()) {
m_Means[j] = data.meanOrMode(j);
m_StdDevs[j] = Math.sqrt(data.variance(j));
if (m_StdDevs[j] == 0) {
m_SelectedAttributes[j] = false;
}
}
}
m_ClassStdDev = Math.sqrt(data.variance(m_TransformedData.classIndex()));
m_ClassMean = data.meanOrMode(m_TransformedData.classIndex());
// Perform the regression
findBestModel();
// Save memory
m_TransformedData = new Instances(data, 0);
}
/** Builds the clusters */
private void buildClusterer() throws Exception {
if (m_trainingSet.classIndex() < 0) m_Clusterer.buildClusterer(m_trainingSet);
else { // class based evaluation if class attribute is set
Remove removeClass = new Remove();
removeClass.setAttributeIndices("" + (m_trainingSet.classIndex() + 1));
removeClass.setInvertSelection(false);
removeClass.setInputFormat(m_trainingSet);
Instances clusterTrain = Filter.useFilter(m_trainingSet, removeClass);
m_Clusterer.buildClusterer(clusterTrain);
}
}
/**
* Constructs an instance suitable for passing to the model for scoring
*
* @param incoming the incoming instance
* @return an instance with values mapped to be consistent with what the model is expecting
*/
protected Instance mapIncomingFieldsToModelFields(Instance incoming) {
Instances modelHeader = m_model.getHeader();
double[] vals = new double[modelHeader.numAttributes()];
for (int i = 0; i < modelHeader.numAttributes(); i++) {
if (m_attributeMap[i] < 0) {
// missing or type mismatch
vals[i] = Utils.missingValue();
continue;
}
Attribute modelAtt = modelHeader.attribute(i);
Attribute incomingAtt = incoming.dataset().attribute(m_attributeMap[i]);
if (incoming.isMissing(incomingAtt.index())) {
vals[i] = Utils.missingValue();
continue;
}
if (modelAtt.isNumeric()) {
vals[i] = incoming.value(m_attributeMap[i]);
} else if (modelAtt.isNominal()) {
String incomingVal = incoming.stringValue(m_attributeMap[i]);
int modelIndex = modelAtt.indexOfValue(incomingVal);
if (modelIndex < 0) {
vals[i] = Utils.missingValue();
} else {
vals[i] = modelIndex;
}
} else if (modelAtt.isString()) {
vals[i] = 0;
modelAtt.setStringValue(incoming.stringValue(m_attributeMap[i]));
}
}
if (modelHeader.classIndex() >= 0) {
// set class to missing value
vals[modelHeader.classIndex()] = Utils.missingValue();
}
Instance newInst = null;
if (incoming instanceof SparseInstance) {
newInst = new SparseInstance(incoming.weight(), vals);
} else {
newInst = new DenseInstance(incoming.weight(), vals);
}
newInst.setDataset(modelHeader);
return newInst;
}
/**
* Determines the output format based on the input format and returns this. In case the output
* format cannot be returned immediately, i.e., hasImmediateOutputFormat() returns false, then
* this method will called from batchFinished() after the call of preprocess(Instances), in which,
* e.g., statistics for the actual processing step can be gathered.
*
* @param inputFormat the input format to base the output format on
* @return the output format
* @throws Exception in case the determination goes wrong
*/
protected Instances determineOutputFormat(Instances inputFormat) throws Exception {
Instances result;
FastVector atts;
int i;
int numAtts;
Vector<Integer> indices;
Vector<Integer> subset;
Random rand;
int index;
// determine the number of attributes
numAtts = inputFormat.numAttributes();
if (inputFormat.classIndex() > -1) numAtts--;
if (m_NumAttributes < 1) {
numAtts = (int) Math.round((double) numAtts * m_NumAttributes);
} else {
if (m_NumAttributes < numAtts) numAtts = (int) m_NumAttributes;
}
if (getDebug()) System.out.println("# of atts: " + numAtts);
// determine random indices
indices = new Vector<Integer>();
for (i = 0; i < inputFormat.numAttributes(); i++) {
if (i == inputFormat.classIndex()) continue;
indices.add(i);
}
subset = new Vector<Integer>();
rand = new Random(m_Seed);
for (i = 0; i < numAtts; i++) {
index = rand.nextInt(indices.size());
subset.add(indices.get(index));
indices.remove(index);
}
Collections.sort(subset);
if (inputFormat.classIndex() > -1) subset.add(inputFormat.classIndex());
if (getDebug()) System.out.println("indices: " + subset);
// generate output format
atts = new FastVector();
m_Indices = new int[subset.size()];
for (i = 0; i < subset.size(); i++) {
atts.addElement(inputFormat.attribute(subset.get(i)));
m_Indices[i] = subset.get(i);
}
result = new Instances(inputFormat.relationName(), atts, 0);
if (inputFormat.classIndex() > -1) result.setClassIndex(result.numAttributes() - 1);
return result;
}
public double ExpectedClassificationError(Instances pool, int attr_i) {
// initialize alpha's to one
int alpha[][][];
int NumberOfFeatures = pool.numAttributes() - 1;
int NumberOfLabels = pool.numClasses();
alpha = new int[NumberOfFeatures][NumberOfLabels][];
for (int i = 0; i < NumberOfFeatures; i++)
for (int j = 0; j < NumberOfLabels; j++) alpha[i][j] = new int[pool.attribute(i).numValues()];
for (int i = 0; i < NumberOfFeatures; i++)
for (int j = 0; j < NumberOfLabels; j++)
for (int k = 0; k < alpha[i][j].length; k++) alpha[i][j][k] = 1;
// construct alpha's
for (int i = 0; i < NumberOfFeatures; i++) // for each attribute
{
if (i == pool.classIndex()) // skip the class attribute
i++;
for (Enumeration<Instance> e = pool.enumerateInstances();
e.hasMoreElements(); ) // for each instance
{
Instance inst = e.nextElement();
if (!inst.isMissing(i)) // if attribute i is not missing (i.e. its been bought)
{
int j = (int) inst.classValue();
int k = (int) inst.value(i);
alpha[i][j][k]++;
}
}
}
return ExpectedClassificationError(alpha, attr_i);
}
/**
* Returns a string representation of the classifier.
*
* @return a string representation of the classifier
*/
public String toString() {
StringBuffer result =
new StringBuffer(
"The independent probability of a class\n--------------------------------------\n");
for (int c = 0; c < m_numClasses; c++)
result
.append(m_headerInfo.classAttribute().value(c))
.append("\t")
.append(Double.toString(m_probOfClass[c]))
.append("\n");
result.append(
"\nThe probability of a word given the class\n-----------------------------------------\n\t");
for (int c = 0; c < m_numClasses; c++)
result.append(m_headerInfo.classAttribute().value(c)).append("\t");
result.append("\n");
for (int w = 0; w < m_numAttributes; w++) {
if (w != m_headerInfo.classIndex()) {
result.append(m_headerInfo.attribute(w).name()).append("\t");
for (int c = 0; c < m_numClasses; c++)
result.append(Double.toString(Math.exp(m_probOfWordGivenClass[c][w]))).append("\t");
result.append("\n");
}
}
return result.toString();
}
/**
* Returns the Capabilities of this filter, customized based on the data. I.e., if removes all
* class capabilities, in case there's not class attribute present or removes the NO_CLASS
* capability, in case that there's a class present.
*
* @param data the data to use for customization
* @return the capabilities of this object, based on the data
* @see #getCapabilities()
*/
public Capabilities getCapabilities(Instances data) {
Capabilities result;
Capabilities classes;
Iterator iter;
Capability cap;
result = getCapabilities();
// no class? -> remove all class capabilites apart from NO_CLASS
if (data.classIndex() == -1) {
classes = result.getClassCapabilities();
iter = classes.capabilities();
while (iter.hasNext()) {
cap = (Capability) iter.next();
if (cap != Capability.NO_CLASS) {
result.disable(cap);
result.disableDependency(cap);
}
}
}
// class? -> remove NO_CLASS
else {
result.disable(Capability.NO_CLASS);
result.disableDependency(Capability.NO_CLASS);
}
return result;
}
/**
* initializes the algorithm
*
* @param data the data to work with
* @throws Exception if m_SVM is null
*/
protected void init(Instances data) throws Exception {
if (m_SVM == null) {
throw new Exception("SVM not initialized in optimizer. Use RegOptimizer.setSVMReg()");
}
m_C = m_SVM.getC();
m_data = data;
m_classIndex = data.classIndex();
m_nInstances = data.numInstances();
// Initialize kernel
m_kernel = Kernel.makeCopy(m_SVM.getKernel());
m_kernel.buildKernel(data);
// init m_target
m_target = new double[m_nInstances];
for (int i = 0; i < m_nInstances; i++) {
m_target[i] = data.instance(i).classValue();
}
m_random = new Random(m_nSeed);
// initialize alpha and alpha* array to all zero
m_alpha = new double[m_target.length];
m_alphaStar = new double[m_target.length];
m_supportVectors = new SMOset(m_nInstances);
m_b = 0.0;
m_nEvals = 0;
m_nCacheHits = -1;
}
/** test the batch saving/loading (via setFile(File)). */
public void testBatch() {
Instances data;
try {
// save
m_Saver.setInstances(m_Instances);
m_Saver.setFile(new File(m_ExportFilename));
m_Saver.writeBatch();
// load
((AbstractFileLoader) m_Loader).setFile(new File(m_ExportFilename));
data = m_Loader.getDataSet();
// compare data
try {
if (m_Instances.classIndex() != data.classIndex()) {
data.setClassIndex(m_Instances.classIndex());
}
compareDatasets(m_Instances, data);
} catch (Exception e) {
fail("Incremental load failed (datasets differ): " + e.toString());
}
} catch (Exception e) {
e.printStackTrace();
fail("Batch save/load failed: " + e.toString());
}
}
/** tests whether a URL can be loaded (via setURL(URL)). */
public void testURLSourcedLoader() {
Instances data;
if (!(getLoader() instanceof URLSourcedLoader)) {
return;
}
try {
// save
m_Saver.setInstances(m_Instances);
m_Saver.setFile(new File(m_ExportFilename));
m_Saver.writeBatch();
// load
((URLSourcedLoader) m_Loader).setURL(new File(m_ExportFilename).toURI().toURL().toString());
data = m_Loader.getDataSet();
// compare data
try {
if (m_Instances.classIndex() != data.classIndex()) {
data.setClassIndex(m_Instances.classIndex());
}
compareDatasets(m_Instances, data);
} catch (Exception e) {
fail("URL load failed (datasets differ): " + e.toString());
}
} catch (Exception e) {
e.printStackTrace();
fail("URL load failed: " + e.toString());
}
}
/**
* Signify that this batch of input to the filter is finished. If the filter requires all
* instances prior to filtering, output() may now be called to retrieve the filtered instances.
*
* @return true if there are instances pending output
* @throws IllegalStateException if no input structure has been defined
*/
public boolean batchFinished() throws Exception {
if (getInputFormat() == null) {
throw new IllegalStateException("No input instance format defined");
}
if (m_attStats == null) {
Instances input = getInputFormat();
m_attStats = new AttributeStats[input.numAttributes()];
for (int i = 0; i < input.numAttributes(); i++) {
if (input.attribute(i).isNumeric() && (input.classIndex() != i)) {
m_attStats[i] = input.attributeStats(i);
}
}
// Convert pending input instances
for (int i = 0; i < input.numInstances(); i++) {
convertInstance(input.instance(i));
}
}
// Free memory
flushInput();
m_NewBatch = true;
return (numPendingOutput() != 0);
}
/** trains the classifier */
@Override
public void train() throws Exception {
if (_train.classIndex() == -1) _train.setClassIndex(_train.numAttributes() - 1);
_cl.buildClassifier(_train);
// evaluate classifier and print some statistics
evaluate();
}
/** tests whether data can be loaded via setSource() with a file stream. */
public void testLoaderWithStream() {
Instances data;
try {
// save
m_Saver.setInstances(m_Instances);
m_Saver.setFile(new File(m_ExportFilename));
m_Saver.writeBatch();
// load
m_Loader.setSource(new FileInputStream(new File(m_ExportFilename)));
data = m_Loader.getDataSet();
// compare data
try {
if (m_Instances.classIndex() != data.classIndex()) {
data.setClassIndex(m_Instances.classIndex());
}
compareDatasets(m_Instances, data);
} catch (Exception e) {
fail("File stream loading failed (datasets differ): " + e.toString());
}
} catch (Exception e) {
e.printStackTrace();
fail("File stream loading failed: " + e.toString());
}
}
/**
* GetKs - return [K_1,K_2,...,K_L] where each Y_j \in {1,...,K_j}. In the multi-label case, K[j]
* = 2 for all j = 1,...,L.
*
* @param D a dataset
* @return an array of the number of values that each label can take
*/
private static int[] getKs(Instances D) {
int L = D.classIndex();
int K[] = new int[L];
for (int k = 0; k < L; k++) {
K[k] = D.attribute(k).numValues();
}
return K;
}
/**
* Return the full data set. If the structure hasn't yet been determined by a call to getStructure
* then method should do so before processing the rest of the data set.
*
* @return the structure of the data set as an empty set of Instances
* @throws IOException if there is no source or parsing fails
*/
public Instances getDataSet() throws IOException {
if (getDirectory() == null) throw new IOException("No directory/source has been specified");
String directoryPath = getDirectory().getAbsolutePath();
ArrayList<String> classes = new ArrayList<String>();
Enumeration enm = getStructure().classAttribute().enumerateValues();
while (enm.hasMoreElements()) classes.add((String) enm.nextElement());
Instances data = getStructure();
int fileCount = 0;
for (int k = 0; k < classes.size(); k++) {
String subdirPath = (String) classes.get(k);
File subdir = new File(directoryPath + File.separator + subdirPath);
String[] files = subdir.list();
for (int j = 0; j < files.length; j++) {
try {
fileCount++;
if (getDebug())
System.err.println("processing " + fileCount + " : " + subdirPath + " : " + files[j]);
double[] newInst = null;
if (m_OutputFilename) newInst = new double[3];
else newInst = new double[2];
File txt =
new File(directoryPath + File.separator + subdirPath + File.separator + files[j]);
BufferedReader is;
if (m_charSet == null || m_charSet.length() == 0) {
is = new BufferedReader(new InputStreamReader(new FileInputStream(txt)));
} else {
is = new BufferedReader(new InputStreamReader(new FileInputStream(txt), m_charSet));
}
StringBuffer txtStr = new StringBuffer();
int c;
while ((c = is.read()) != -1) {
txtStr.append((char) c);
}
newInst[0] = (double) data.attribute(0).addStringValue(txtStr.toString());
if (m_OutputFilename)
newInst[1] =
(double) data.attribute(1).addStringValue(subdirPath + File.separator + files[j]);
newInst[data.classIndex()] = (double) k;
data.add(new DenseInstance(1.0, newInst));
is.close();
} catch (Exception e) {
System.err.println(
"failed to convert file: "
+ directoryPath
+ File.separator
+ subdirPath
+ File.separator
+ files[j]);
}
}
}
return data;
}
/** evaluates the classifier */
@Override
public void evaluate() throws Exception {
// evaluate classifier and print some statistics
if (_test.classIndex() == -1) _test.setClassIndex(_test.numAttributes() - 1);
Evaluation eval = new Evaluation(_train);
eval.evaluateModel(_cl, _test);
System.out.println(eval.toSummaryString("\nResults\n======\n", false));
System.out.println(eval.toMatrixString());
}
public static void main(String[] args) throws Exception {
BufferedReader reader = new BufferedReader(new FileReader("PCAin.arff"));
Instances data = new Instances(reader);
reader.close();
if (data.classIndex() == -1) {
data.setClassIndex(data.numAttributes() - 1);
}
pca(data);
}
/**
* Searches the attribute subset space using a genetic algorithm.
*
* @param ASEval the attribute evaluator to guide the search
* @param data the training instances.
* @return an array (not necessarily ordered) of selected attribute indexes
* @throws Exception if the search can't be completed
*/
@Override
public int[] search(ASEvaluation ASEval, Instances data) throws Exception {
m_best = null;
m_generationReports = new StringBuffer();
if (!(ASEval instanceof SubsetEvaluator)) {
throw new Exception(ASEval.getClass().getName() + " is not a " + "Subset evaluator!");
}
if (ASEval instanceof UnsupervisedSubsetEvaluator) {
m_hasClass = false;
} else {
m_hasClass = true;
m_classIndex = data.classIndex();
}
SubsetEvaluator ASEvaluator = (SubsetEvaluator) ASEval;
m_numAttribs = data.numAttributes();
m_startRange.setUpper(m_numAttribs - 1);
if (!(getStartSet().equals(""))) {
m_starting = m_startRange.getSelection();
}
// initial random population
m_lookupTable = new Hashtable<BitSet, GABitSet>(m_lookupTableSize);
m_random = new Random(m_seed);
m_population = new GABitSet[m_popSize];
// set up random initial population
initPopulation();
evaluatePopulation(ASEvaluator);
populationStatistics();
scalePopulation();
checkBest();
m_generationReports.append(populationReport(0));
boolean converged;
for (int i = 1; i <= m_maxGenerations; i++) {
generation();
evaluatePopulation(ASEvaluator);
populationStatistics();
scalePopulation();
// find the best pop member and check for convergence
converged = checkBest();
if ((i == m_maxGenerations) || ((i % m_reportFrequency) == 0) || (converged == true)) {
m_generationReports.append(populationReport(i));
if (converged == true) {
break;
}
}
}
return attributeList(m_best.getChromosome());
}
/**
* Method for building this classifier. Since the collective classifiers also need the test set,
* we only store here the training set.
*
* @param training the training set to use
* @throws Exception derived classes may throw Exceptions
*/
public void buildClassifier(Instances training) throws Exception {
m_ClassifierBuilt = false;
m_Trainset = training;
// set class index?
if (m_Trainset.classIndex() == -1) m_Trainset.setClassIndex(m_Trainset.numAttributes() - 1);
// necessary for JUnit tests
checkRestrictions();
}
/**
* Determines the output format based on the input format and returns this. In case the output
* format cannot be returned immediately, i.e., immediateOutputFormat() returns false, then this
* method will be called from batchFinished().
*
* @param inputFormat the input format to base the output format on
* @return the output format
* @throws Exception in case the determination goes wrong
* @see #hasImmediateOutputFormat()
* @see #batchFinished()
*/
protected Instances determineOutputFormat(Instances inputFormat) throws Exception {
Instances data;
Instances result;
FastVector atts;
FastVector values;
HashSet hash;
int i;
int n;
boolean isDate;
Instance inst;
Vector sorted;
m_Cols.setUpper(inputFormat.numAttributes() - 1);
data = new Instances(inputFormat);
atts = new FastVector();
for (i = 0; i < data.numAttributes(); i++) {
if (!m_Cols.isInRange(i) || !data.attribute(i).isNumeric()) {
atts.addElement(data.attribute(i));
continue;
}
// date attribute?
isDate = (data.attribute(i).type() == Attribute.DATE);
// determine all available attribtues in dataset
hash = new HashSet();
for (n = 0; n < data.numInstances(); n++) {
inst = data.instance(n);
if (inst.isMissing(i)) continue;
if (isDate) hash.add(inst.stringValue(i));
else hash.add(new Double(inst.value(i)));
}
// sort values
sorted = new Vector();
for (Object o : hash) sorted.add(o);
Collections.sort(sorted);
// create attribute from sorted values
values = new FastVector();
for (Object o : sorted) {
if (isDate) values.addElement(o.toString());
else values.addElement(Utils.doubleToString(((Double) o).doubleValue(), MAX_DECIMALS));
}
atts.addElement(new Attribute(data.attribute(i).name(), values));
}
result = new Instances(inputFormat.relationName(), atts, 0);
result.setClassIndex(inputFormat.classIndex());
return result;
}
private static void evaluateClassifier(Classifier c, Instances trainData, Instances testData)
throws Exception {
System.err.println(
"INFO: Starting split validation to predict '"
+ trainData.classAttribute().name()
+ "' using '"
+ c.getClass().getCanonicalName()
+ ":"
+ Arrays.toString(c.getOptions())
+ "' (#train="
+ trainData.numInstances()
+ ",#test="
+ testData.numInstances()
+ ") ...");
if (trainData.classIndex() < 0) throw new IllegalStateException("class attribute not set");
c.buildClassifier(trainData);
Evaluation eval = new Evaluation(testData);
eval.useNoPriors();
double[] predictions = eval.evaluateModel(c, testData);
System.out.println(eval.toClassDetailsString());
System.out.println(eval.toSummaryString("\nResults\n======\n", false));
// write predictions to file
{
System.err.println("INFO: Writing predictions to file ...");
Writer out = new FileWriter("prediction.trec");
writePredictionsTrecEval(predictions, testData, 0, trainData.classIndex(), out);
out.close();
}
// write predicted distributions to CSV
{
System.err.println("INFO: Writing predicted distributions to CSV ...");
Writer out = new FileWriter("predicted_distribution.csv");
writePredictedDistributions(c, testData, 0, out);
out.close();
}
}
/**
* Calculates the distance between two instances
*
* @param test the first instance
* @param train the second instance
* @return the distance between the two given instances, between 0 and 1
*/
protected double distance(Instance first, Instance second) {
double distance = 0;
int firstI, secondI;
for (int p1 = 0, p2 = 0; p1 < first.numValues() || p2 < second.numValues(); ) {
if (p1 >= first.numValues()) {
firstI = m_instances.numAttributes();
} else {
firstI = first.index(p1);
}
if (p2 >= second.numValues()) {
secondI = m_instances.numAttributes();
} else {
secondI = second.index(p2);
}
if (firstI == m_instances.classIndex()) {
p1++;
continue;
}
if (secondI == m_instances.classIndex()) {
p2++;
continue;
}
double diff;
if (firstI == secondI) {
diff = difference(firstI, first.valueSparse(p1), second.valueSparse(p2));
p1++;
p2++;
} else if (firstI > secondI) {
diff = difference(secondI, 0, second.valueSparse(p2));
p2++;
} else {
diff = difference(firstI, first.valueSparse(p1), 0);
p1++;
}
distance += diff * diff;
}
return Math.sqrt(distance / m_instances.numAttributes());
}
/**
* processes the instances using the HAAR algorithm
*
* @param instances the data to process
* @return the modified data
* @throws Exception in case the processing goes wrong
*/
protected Instances processHAAR(Instances instances) throws Exception {
Instances result;
int i;
int n;
int j;
int clsIdx;
double[] oldVal;
double[] newVal;
int level;
int length;
double[] clsVal;
Attribute clsAtt;
clsIdx = instances.classIndex();
clsVal = null;
clsAtt = null;
if (clsIdx > -1) {
clsVal = instances.attributeToDoubleArray(clsIdx);
clsAtt = (Attribute) instances.classAttribute().copy();
instances.setClassIndex(-1);
instances.deleteAttributeAt(clsIdx);
}
result = new Instances(instances, 0);
level = (int) StrictMath.ceil(StrictMath.log(instances.numAttributes()) / StrictMath.log(2.0));
for (i = 0; i < instances.numInstances(); i++) {
oldVal = instances.instance(i).toDoubleArray();
newVal = new double[oldVal.length];
for (n = level; n > 0; n--) {
length = (int) StrictMath.pow(2, n - 1);
for (j = 0; j < length; j++) {
newVal[j] = (oldVal[j * 2] + oldVal[j * 2 + 1]) / StrictMath.sqrt(2);
newVal[j + length] = (oldVal[j * 2] - oldVal[j * 2 + 1]) / StrictMath.sqrt(2);
}
System.arraycopy(newVal, 0, oldVal, 0, newVal.length);
}
// add new transformed instance
result.add(new DenseInstance(1, newVal));
}
// add class again
if (clsIdx > -1) {
result.insertAttributeAt(clsAtt, clsIdx);
result.setClassIndex(clsIdx);
for (i = 0; i < clsVal.length; i++) result.instance(i).setClassValue(clsVal[i]);
}
return result;
}
// use the learned classifiers to get conditional probability
protected double conMI(Instances D_j, Instances D_k, CNode[][] miNodes, int j, int k)
throws Exception {
int L = D_j.classIndex();
int N = D_j.numInstances();
double y[] = new double[L];
double I = 0.0; // conditional mutual information for y_j and y_k
double p_1, p_2; // p( y_j = 1 | x ), p( y_j = 2 | x )
double p_12[] = {
0.0, 0.0
}; // p_12[0] = p( y_j = 1 | y_k = 0, x ) and p_12[1] = p( y_j = 1 | y_k = 1, x )
for (int i = 0; i < N; i++) {
Arrays.fill(y, 0);
p_1 =
Math.max(
miNodes[j][0].distribution((Instance) D_j.instance(i).copy(), y)[1],
0.000001); // p( y_j = 1 | x )
p_1 = Math.min(p_1, 0.999999);
p_1 = Math.max(p_1, 0.000001);
Arrays.fill(y, 0);
p_2 =
Math.max(
miNodes[k][0].distribution((Instance) D_k.instance(i).copy(), y)[1],
0.000001); // p( y_k = 1 | x )
p_2 = Math.min(p_2, 0.999999);
p_2 = Math.max(p_2, 0.000001);
Arrays.fill(y, 0);
p_12[0] =
Math.max(
miNodes[j][k - j].distribution((Instance) D_j.instance(i).copy(), y)[1],
0.000001); // p( y_j = 1 | y_k = 0, x )
p_12[0] = Math.min(p_12[0], 0.999999);
p_12[0] = Math.max(p_12[0], 0.000001);
Arrays.fill(y, 0);
Arrays.fill(y, k, k + 1, 1.0);
p_12[1] =
Math.max(
miNodes[j][k - j].distribution((Instance) D_j.instance(i).copy(), y)[1],
0.000001); // p( y_j = 1 | y_k = 1, x )
p_12[1] = Math.min(p_12[1], 0.999999);
p_12[1] = Math.max(p_12[1], 0.000001);
I +=
(1 - p_12[0]) * (1 - p_2) * Math.log((1 - p_12[0]) / (1 - p_1)); // I( y_j = 0 ; y_k = 0 )
I += (1 - p_12[1]) * (p_2) * Math.log((1 - p_12[1]) / (1 - p_1)); // I( y_j = 0 ; y_k = 1 )
I += (p_12[0]) * (1 - p_2) * Math.log((p_12[0]) / (p_1)); // I( y_j = 1 ; y_k = 0 )
I += (p_12[1]) * (p_2) * Math.log((p_12[1]) / (p_1)); // I( y_j = 1 ; y_k = 0 )
}
I = I / N;
return I;
}
@Override
public void train(Instances instance) {
// find the best attribute
int classIdx = instance.classIndex();
for (int i = 0; i < instance.numInstances(); i++) {
if (classIdx == 0) {
zeroIns.add(instance.instance(i));
} else {
oneIns.add(instance.instance(i));
}
}
}
/**
* Transform.
*
* @param D original Instances
* @param c to be the class Attribute
* @param pa_c the parent indices of c
* @return new Instances T
*/
public static Instances transform(Instances D, int c, int pa_c[]) throws Exception {
int L = D.classIndex();
int keep[] = A.append(pa_c, c); // keep all parents and self!
Arrays.sort(keep);
int remv[] = A.invert(keep, L); // i.e., remove the rest < L
Arrays.sort(remv);
Instances T = F.remove(new Instances(D), remv, false);
int map[] = new int[L];
for (int j = 0; j < L; j++) {
map[j] = Arrays.binarySearch(keep, j);
}
T.setClassIndex(map[c]);
return T;
}
/**
* Sets the format of the input instances.
*
* @param instanceInfo an Instances object containing the input instance structure (any instances
* contained in the object are ignored - only the structure is required).
* @return true if the outputFormat may be collected immediately
* @throws Exception if the input format can't be set successfully
*/
public boolean setInputFormat(Instances instanceInfo) throws Exception {
super.setInputFormat(instanceInfo);
m_AttIndex.setUpper(instanceInfo.numAttributes() - 1);
m_FirstIndex.setUpper(instanceInfo.attribute(m_AttIndex.getIndex()).numValues() - 1);
m_SecondIndex.setUpper(instanceInfo.attribute(m_AttIndex.getIndex()).numValues() - 1);
if ((instanceInfo.classIndex() > -1) && (instanceInfo.classIndex() == m_AttIndex.getIndex())) {
throw new Exception("Cannot process class attribute.");
}
if (!instanceInfo.attribute(m_AttIndex.getIndex()).isNominal()) {
throw new UnsupportedAttributeTypeException("Chosen attribute not nominal.");
}
if (instanceInfo.attribute(m_AttIndex.getIndex()).numValues() < 2) {
throw new UnsupportedAttributeTypeException(
"Chosen attribute has less than " + "two values.");
}
if (m_SecondIndex.getIndex() <= m_FirstIndex.getIndex()) {
// XXX Maybe we should just swap the values??
throw new Exception("The second index has to be greater " + "than the first.");
}
setOutputFormat();
return true;
}
