/**
* Process a classifier's prediction for an instance and update a set of plotting instances and
* additional plotting info. m_PlotShape for nominal class datasets holds shape types (actual data
* points have automatic shape type assignment; classifier error data points have box shape type).
* For numeric class datasets, the actual data points are stored in m_PlotInstances and m_PlotSize
* stores the error (which is later converted to shape size values).
*
* @param toPredict the actual data point
* @param classifier the classifier
* @param eval the evaluation object to use for evaluating the classifier on the instance to
* predict
* @see #m_PlotShapes
* @see #m_PlotSizes
* @see #m_PlotInstances
*/
public void process(Instance toPredict, Classifier classifier, Evaluation eval) {
double pred;
double[] values;
int i;
try {
pred = eval.evaluateModelOnceAndRecordPrediction(classifier, toPredict);
if (classifier instanceof weka.classifiers.misc.InputMappedClassifier) {
toPredict =
((weka.classifiers.misc.InputMappedClassifier) classifier)
.constructMappedInstance(toPredict);
}
if (!m_SaveForVisualization) return;
if (m_PlotInstances != null) {
values = new double[m_PlotInstances.numAttributes()];
for (i = 0; i < m_PlotInstances.numAttributes(); i++) {
if (i < toPredict.classIndex()) {
values[i] = toPredict.value(i);
} else if (i == toPredict.classIndex()) {
values[i] = pred;
values[i + 1] = toPredict.value(i);
i++;
} else {
values[i] = toPredict.value(i - 1);
}
}
m_PlotInstances.add(new DenseInstance(1.0, values));
if (toPredict.classAttribute().isNominal()) {
if (toPredict.isMissing(toPredict.classIndex()) || Utils.isMissingValue(pred)) {
m_PlotShapes.addElement(new Integer(Plot2D.MISSING_SHAPE));
} else if (pred != toPredict.classValue()) {
// set to default error point shape
m_PlotShapes.addElement(new Integer(Plot2D.ERROR_SHAPE));
} else {
// otherwise set to constant (automatically assigned) point shape
m_PlotShapes.addElement(new Integer(Plot2D.CONST_AUTOMATIC_SHAPE));
}
m_PlotSizes.addElement(new Integer(Plot2D.DEFAULT_SHAPE_SIZE));
} else {
// store the error (to be converted to a point size later)
Double errd = null;
if (!toPredict.isMissing(toPredict.classIndex()) && !Utils.isMissingValue(pred)) {
errd = new Double(pred - toPredict.classValue());
m_PlotShapes.addElement(new Integer(Plot2D.CONST_AUTOMATIC_SHAPE));
} else {
// missing shape if actual class not present or prediction is missing
m_PlotShapes.addElement(new Integer(Plot2D.MISSING_SHAPE));
}
m_PlotSizes.addElement(errd);
}
}
} catch (Exception ex) {
ex.printStackTrace();
}
}
@Override
boolean evaluate(
Instance inst,
int lhsAttIndex,
String rhsOperand,
double numericOperand,
Pattern regexPattern,
boolean rhsIsAttribute,
int rhsAttIndex) {
if (rhsIsAttribute) {
if (inst.isMissing(lhsAttIndex) && inst.isMissing(rhsAttIndex)) {
return true;
}
if (inst.isMissing(lhsAttIndex) || inst.isMissing(rhsAttIndex)) {
return false;
}
return Utils.eq(inst.value(lhsAttIndex), inst.value(rhsAttIndex));
}
if (inst.isMissing(lhsAttIndex)) {
return false;
}
return (Utils.eq(inst.value(lhsAttIndex), numericOperand));
}
/**
* Compare two datasets to see if they differ.
*
* @param data1 one set of instances
* @param data2 the other set of instances
* @throws Exception if the datasets differ
*/
protected void compareDatasets(Instances data1, Instances data2) throws Exception {
if (m_CheckHeader) {
if (!data2.equalHeaders(data1)) {
throw new Exception("header has been modified\n" + data2.equalHeadersMsg(data1));
}
}
if (!(data2.numInstances() == data1.numInstances())) {
throw new Exception("number of instances has changed");
}
for (int i = 0; i < data2.numInstances(); i++) {
Instance orig = data1.instance(i);
Instance copy = data2.instance(i);
for (int j = 0; j < orig.numAttributes(); j++) {
if (orig.isMissing(j)) {
if (!copy.isMissing(j)) {
throw new Exception("instances have changed");
}
} else {
if (m_CompareValuesAsString) {
if (!orig.toString(j).equals(copy.toString(j))) {
throw new Exception("instances have changed");
}
} else {
if (Math.abs(orig.value(j) - copy.value(j)) > m_MaxDiffValues) {
throw new Exception("instances have changed");
}
}
}
if (Math.abs(orig.weight() - copy.weight()) > m_MaxDiffWeights) {
throw new Exception("instance weights have changed");
}
}
}
}
/**
* Convert a single instance over. The converted instance is added to the end of the output queue.
*
* @param instance the instance to convert
*/
protected void convertInstance(Instance instance) {
int index = 0;
double[] vals = new double[outputFormatPeek().numAttributes()];
// Copy and convert the values
for (int i = 0; i < getInputFormat().numAttributes(); i++) {
if (m_DiscretizeCols.isInRange(i) && getInputFormat().attribute(i).isNumeric()) {
int j;
double currentVal = instance.value(i);
if (m_CutPoints[i] == null) {
if (instance.isMissing(i)) {
vals[index] = Utils.missingValue();
} else {
vals[index] = 0;
}
index++;
} else {
if (!m_MakeBinary) {
if (instance.isMissing(i)) {
vals[index] = Utils.missingValue();
} else {
for (j = 0; j < m_CutPoints[i].length; j++) {
if (currentVal <= m_CutPoints[i][j]) {
break;
}
}
vals[index] = j;
}
index++;
} else {
for (j = 0; j < m_CutPoints[i].length; j++) {
if (instance.isMissing(i)) {
vals[index] = Utils.missingValue();
} else if (currentVal <= m_CutPoints[i][j]) {
vals[index] = 0;
} else {
vals[index] = 1;
}
index++;
}
}
}
} else {
vals[index] = instance.value(i);
index++;
}
}
Instance inst = null;
if (instance instanceof SparseInstance) {
inst = new SparseInstance(instance.weight(), vals);
} else {
inst = new DenseInstance(instance.weight(), vals);
}
inst.setDataset(getOutputFormat());
copyValues(inst, false, instance.dataset(), getOutputFormat());
inst.setDataset(getOutputFormat());
push(inst);
}
public void testTypical() {
m_Filter = getFilter("6,3");
Instances result = useFilter();
assertEquals(m_Instances.numAttributes() - 1, result.numAttributes());
for (int i = 0; i < result.numInstances(); i++) {
Instance orig = m_Instances.instance(i);
if (orig.isMissing(5) || orig.isMissing(2)) {
assertTrue("Instance " + (i + 1) + " should have been ?", result.instance(i).isMissing(4));
} else {
assertEquals(orig.value(5) - orig.value(2), result.instance(i).value(4), EXPR_DELTA);
}
}
}
/**
* Input an instance for filtering. Ordinarily the instance is processed and made available for
* output immediately. Some filters require all instances be read before producing output.
*
* @param instance the input instance
* @return true if the filtered instance may now be collected with output().
* @exception IllegalStateException if no input format has been defined.
* @exception Exception if there was a problem during the filtering.
*/
public boolean input(Instance instance) throws Exception {
if (getInputFormat() == null) {
throw new IllegalStateException("No input instance format defined");
}
if (m_NewBatch) {
resetQueue();
m_NewBatch = false;
}
double[] vals = new double[instance.numAttributes() + 1];
for (int i = 0; i < instance.numAttributes(); i++) {
if (instance.isMissing(i)) {
vals[i] = Instance.missingValue();
} else {
vals[i] = instance.value(i);
}
}
evaluateExpression(vals);
Instance inst = null;
if (instance instanceof SparseInstance) {
inst = new SparseInstance(instance.weight(), vals);
} else {
inst = new Instance(instance.weight(), vals);
}
copyStringValues(inst, false, instance.dataset(), getOutputFormat());
inst.setDataset(getOutputFormat());
push(inst);
return true;
}
/**
* Input an instance for filtering.
*
* @param instance the input instance
* @return true if the filtered instance may now be collected with output().
* @throws Exception if the input format was not set or the date format cannot be parsed
*/
public boolean input(Instance instance) throws Exception {
if (getInputFormat() == null) {
throw new IllegalStateException("No input instance format defined");
}
if (m_NewBatch) {
resetQueue();
m_NewBatch = false;
}
Instance newInstance = (Instance) instance.copy();
int index = m_AttIndex.getIndex();
if (!newInstance.isMissing(index)) {
double value = instance.value(index);
try {
// Format and parse under the new format to force any required
// loss in precision.
value = m_OutputAttribute.parseDate(m_OutputAttribute.formatDate(value));
} catch (ParseException pe) {
throw new RuntimeException("Output date format couldn't parse its own output!!");
}
newInstance.setValue(index, value);
}
push(newInstance);
return true;
}
/** Computes average class values for each attribute and value */
private void computeAverageClassValues() {
double totalCounts, sum;
Instance instance;
double[] counts;
double[][] avgClassValues = new double[getInputFormat().numAttributes()][0];
m_Indices = new int[getInputFormat().numAttributes()][0];
for (int j = 0; j < getInputFormat().numAttributes(); j++) {
Attribute att = getInputFormat().attribute(j);
if (att.isNominal()) {
avgClassValues[j] = new double[att.numValues()];
counts = new double[att.numValues()];
for (int i = 0; i < getInputFormat().numInstances(); i++) {
instance = getInputFormat().instance(i);
if (!instance.classIsMissing() && (!instance.isMissing(j))) {
counts[(int) instance.value(j)] += instance.weight();
avgClassValues[j][(int) instance.value(j)] += instance.weight() * instance.classValue();
}
}
sum = Utils.sum(avgClassValues[j]);
totalCounts = Utils.sum(counts);
if (Utils.gr(totalCounts, 0)) {
for (int k = 0; k < att.numValues(); k++) {
if (Utils.gr(counts[k], 0)) {
avgClassValues[j][k] /= counts[k];
} else {
avgClassValues[j][k] = sum / totalCounts;
}
}
}
m_Indices[j] = Utils.sort(avgClassValues[j]);
}
}
}
@Override
boolean evaluate(
Instance inst,
int lhsAttIndex,
String rhsOperand,
double numericOperand,
Pattern regexPattern,
boolean rhsIsAttribute,
int rhsAttIndex) {
if (inst.isMissing(lhsAttIndex)) {
return false;
}
if (regexPattern == null) {
return false;
}
String lhsString = "";
try {
lhsString = inst.stringValue(lhsAttIndex);
} catch (IllegalArgumentException ex) {
return false;
}
return regexPattern.matcher(lhsString).matches();
}
/**
* Convert an input instance
*
* @param current the input instance to convert
* @return a transformed instance
* @throws Exception if a problem occurs
*/
protected Instance convertInstance(Instance current) throws Exception {
double[] vals = new double[getOutputFormat().numAttributes()];
int index = 0;
for (int j = 0; j < current.numAttributes(); j++) {
if (j != current.classIndex()) {
if (m_unchanged != null && m_unchanged.attribute(current.attribute(j).name()) != null) {
vals[index++] = current.value(j);
} else {
Estimator[] estForAtt = m_estimatorLookup.get(current.attribute(j).name());
for (int k = 0; k < current.classAttribute().numValues(); k++) {
if (current.isMissing(j)) {
vals[index++] = Utils.missingValue();
} else {
double e = estForAtt[k].getProbability(current.value(j));
vals[index++] = e;
}
}
}
}
}
vals[vals.length - 1] = current.classValue();
DenseInstance instNew = new DenseInstance(current.weight(), vals);
return instNew;
}
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);
}
/**
* Calculates the class membership probabilities for the given test instance.
*
* @param instance the instance to be classified
* @return predicted class probability distribution
* @exception Exception if distribution can't be computed
*/
@Override
public double[] distributionForInstance(Instance instance) throws Exception {
double[] probs = new double[instance.numClasses()];
int attIndex;
for (int j = 0; j < instance.numClasses(); j++) {
probs[j] = 1;
Enumeration<Attribute> enumAtts = instance.enumerateAttributes();
attIndex = 0;
while (enumAtts.hasMoreElements()) {
Attribute attribute = enumAtts.nextElement();
if (!instance.isMissing(attribute)) {
if (attribute.isNominal()) {
probs[j] *= m_Counts[j][attIndex][(int) instance.value(attribute)];
} else {
probs[j] *=
normalDens(instance.value(attribute), m_Means[j][attIndex], m_Devs[j][attIndex]);
}
}
attIndex++;
}
probs[j] *= m_Priors[j];
}
// Normalize probabilities
Utils.normalize(probs);
return probs;
}
public int SelectRow_First(Instances pool, int desiredAttr, int desiredLabel) {
// buy the desiredAttr-th attribute of an (the first) instance with label argmin_j;
for (int i = 0; i < pool.numInstances(); i++) {
Instance inst = pool.instance(i);
if ((int) inst.classValue() == desiredLabel && inst.isMissing(desiredAttr)) return i;
}
return -1;
}
public int SelectRow_First(Instances pool, int desiredAttr) {
// buy the desiredAttr-th attribute of an (the first) instance regardless of label
for (int i = 0; i < pool.numInstances(); i++) {
Instance inst = pool.instance(i);
if (inst.isMissing(desiredAttr)) return i;
}
return -1;
}
public int SelectRow_KLDivergenceMisclassified(
Instances pool, Classifier myEstimator, int desiredAttr) {
// for each instance with unbought desiredAttr and label = desiredLabel
// measure KL-divergence (relative entropy between two prob distributions):
// KL(P||Q) = sum_i p_i log (p_i/q_i)
// withr respect to Q = Uniform, we have
// KL(P||U) = sum_i p_i log(p_i)
// choose (row) that is minimum (i.e. closest to uniform)
int numInstances = pool.numInstances();
double[] KLDivs = new double[numInstances];
boolean[] isValidInstance = new boolean[numInstances];
boolean misclassified = false;
double[] probs = null;
Instance inst;
for (int i = 0; i < numInstances; i++) {
inst = pool.instance(i);
try {
if (inst.classValue() != myEstimator.classifyInstance(inst)) misclassified = true;
else misclassified = false;
} catch (Exception e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
if (inst.isMissing(desiredAttr) && misclassified) {
try {
probs = myEstimator.distributionForInstance(inst);
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
for (int j = 0; j < probs.length; j++) KLDivs[i] += MyXLogX(probs[j]);
isValidInstance[i] = true;
} else {
KLDivs[i] = Double.MAX_VALUE;
isValidInstance[i] = false;
}
}
double leastDivergence = KLDivs[Utils.minIndex(KLDivs)];
int numLeastDivs = 0;
for (int i = 0; i < numInstances; i++)
if (isValidInstance[i] && KLDivs[i] == leastDivergence) numLeastDivs++;
int randomInstance = r.nextInt(numLeastDivs);
int index = 0;
for (int i = 0; i < numInstances; i++) {
if (isValidInstance[i] && KLDivs[i] == leastDivergence) {
if (index == randomInstance) return i;
else index++;
}
}
return -1;
}
/**
* Returns index of subset instance is assigned to. Returns -1 if instance is assigned to more
* than one subset.
*
* @exception Exception if something goes wrong
*/
public final int whichSubset(Instance instance) throws Exception {
if (instance.isMissing(m_attIndex)) return -1;
else {
if (instance.attribute(m_attIndex).isNominal()) {
if ((int) m_splitPoint == (int) instance.value(m_attIndex)) return 0;
else return 1;
} else if (Utils.smOrEq(instance.value(m_attIndex), m_splitPoint)) return 0;
else return 1;
}
}
public double classifyInstance(Instance inst) throws Exception {
if (m_attribute == null) {
return m_intercept;
} else {
if (inst.isMissing(m_attribute.index())) {
throw new Exception("UnivariateLinearRegression: No missing values!");
}
return m_intercept + m_slope * inst.value(m_attribute.index());
}
}
/**
* 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;
}
/**
* method to set a new value
*
* @param r random function
* @param numOfValues
* @param instance
* @param useMissing
*/
private void changeValueRandomly(
Random r, int numOfValues, int indexOfAtt, Instance instance, boolean useMissing) {
int currValue;
// get current value
// if value is missing set current value to number of values
// whiche is the highest possible value plus one
if (instance.isMissing(indexOfAtt)) {
currValue = numOfValues;
} else {
currValue = (int) instance.value(indexOfAtt);
}
// with only two possible values it is easier
if ((numOfValues == 2) && (!instance.isMissing(indexOfAtt))) {
instance.setValue(indexOfAtt, (double) ((currValue + 1) % 2));
} else {
// get randomly a new value not equal to the current value
// if missing values are used as values they must be treated
// in a special way
while (true) {
int newValue;
if (useMissing) {
newValue = (int) (r.nextDouble() * (double) (numOfValues + 1));
} else {
newValue = (int) (r.nextDouble() * (double) numOfValues);
}
// have we found a new value?
if (newValue != currValue) {
// the value 1 above the highest possible value (=numOfValues)
// is used as missing value
if (newValue == numOfValues) {
instance.setMissing(indexOfAtt);
} else {
instance.setValue(indexOfAtt, (double) newValue);
}
break;
}
}
}
}
@Override
boolean evaluate(
Instance inst,
int lhsAttIndex,
String rhsOperand,
double numericOperand,
Pattern regexPattern,
boolean rhsIsAttribute,
int rhsAttIndex) {
return (inst.isMissing(lhsAttIndex));
}
/**
* 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;
}
public int SelectRow_Random(Instances pool, int desiredAttr) {
// randomly select among instances with
// -unbought desiredAttr and
// -desiredLabel
int numberValidInstances = 0;
for (int i = 0; i < pool.numInstances(); i++) {
Instance inst = pool.instance(i);
if (inst.isMissing(desiredAttr)) numberValidInstances++;
}
if (numberValidInstances == 0) return -1;
int randomInstance = r.nextInt(numberValidInstances);
int index = 0;
for (int i = 0; i < pool.numInstances(); i++) {
Instance inst = pool.instance(i);
if (inst.isMissing(desiredAttr)) {
if (index == randomInstance) return i;
else index++;
}
}
return -1;
}
/**
* Compare two datasets to see if they differ.
*
* @param data1 one set of instances
* @param data2 the other set of instances
* @throws Exception if the datasets differ
*/
protected void compareDatasets(Instances data1, Instances data2) throws Exception {
if (data1.numAttributes() != data2.numAttributes())
throw new Exception("number of attributes has changed");
if (!(data2.numInstances() == data1.numInstances()))
throw new Exception("number of instances has changed");
for (int i = 0; i < data2.numInstances(); i++) {
Instance orig = data1.instance(i);
Instance copy = data2.instance(i);
for (int j = 0; j < orig.numAttributes(); j++) {
if (orig.isMissing(j)) {
if (!copy.isMissing(j)) throw new Exception("instances have changed");
} else if (!orig.toString(j).equals(copy.toString(j))) {
throw new Exception("instances have changed");
}
if (orig.weight() != copy.weight()) throw new Exception("instance weights have changed");
}
}
}
/**
* Checks if an instance contains an item set.
*
* @param instance the instance to be tested
* @return true if the given instance contains this item set
*/
public boolean containedByTreatZeroAsMissing(Instance instance) {
if (instance instanceof weka.core.SparseInstance) {
int numInstVals = instance.numValues();
int numItemSetVals = m_items.length;
for (int p1 = 0, p2 = 0; p1 < numInstVals || p2 < numItemSetVals; ) {
int instIndex = Integer.MAX_VALUE;
if (p1 < numInstVals) {
instIndex = instance.index(p1);
}
int itemIndex = p2;
if (m_items[itemIndex] > -1) {
if (itemIndex != instIndex) {
return false;
} else {
if (instance.isMissingSparse(p1)) {
return false;
}
if (m_items[itemIndex] != (int) instance.valueSparse(p1)) {
return false;
}
}
p1++;
p2++;
} else {
if (itemIndex < instIndex) {
p2++;
} else if (itemIndex == instIndex) {
p2++;
p1++;
}
}
}
} else {
for (int i = 0; i < instance.numAttributes(); i++) {
if (m_items[i] > -1) {
if (instance.isMissing(i) || (int) instance.value(i) == 0) {
return false;
}
if (m_items[i] != (int) instance.value(i)) {
return false;
}
}
}
}
return true;
}
/**
* Returns weights if instance is assigned to more than one subset. Returns null if instance is
* only assigned to one subset.
*/
public final double[] weights(Instance instance) {
double[] weights;
int i;
if (instance.isMissing(m_attIndex)) {
weights = new double[m_numSubsets];
for (i = 0; i < m_numSubsets; i++)
weights[i] = m_distribution.perBag(i) / m_distribution.total();
return weights;
} else {
return null;
}
}
/**
* Gets the subset of instances that apply to a particluar branch of the split. If the branch
* index is -1, the subset will consist of those instances that don't apply to any branch.
*
* @param branch the index of the branch
* @param sourceInstances the instances from which to find the subset
* @return the set of instances that apply
*/
public ReferenceInstances instancesDownBranch(int branch, Instances instances) {
ReferenceInstances filteredInstances = new ReferenceInstances(instances, 1);
if (branch == -1) {
for (Enumeration e = instances.enumerateInstances(); e.hasMoreElements(); ) {
Instance inst = (Instance) e.nextElement();
if (inst.isMissing(attIndex)) filteredInstances.addReference(inst);
}
} else if (branch == 0) {
for (Enumeration e = instances.enumerateInstances(); e.hasMoreElements(); ) {
Instance inst = (Instance) e.nextElement();
if (!inst.isMissing(attIndex) && inst.value(attIndex) < splitPoint)
filteredInstances.addReference(inst);
}
} else {
for (Enumeration e = instances.enumerateInstances(); e.hasMoreElements(); ) {
Instance inst = (Instance) e.nextElement();
if (!inst.isMissing(attIndex) && inst.value(attIndex) >= splitPoint)
filteredInstances.addReference(inst);
}
}
return filteredInstances;
}
/**
* Checks if an instance contains an item set.
*
* @param instance the instance to be tested
* @return true if the given instance contains this item set
*/
public boolean containedBy(Instance instance) {
for (int i = 0; i < instance.numAttributes(); i++) {
if (m_items[i] > -1) {
if (instance.isMissing(i)) {
return false;
}
if (m_items[i] != (int) instance.value(i)) {
return false;
}
}
}
return true;
}
int SelectRow_ErrorMargin(Instances pool, Classifier myEstimator, int desiredAttr) {
// for each instance with unbought desiredAttr and label = desiredLabel
// measure Prob(i,L(i)) the class probability of the true label, choose the one minimizing it.
// i.e. the most erroneous instance
int numInstances = pool.numInstances();
double[] classProb = new double[numInstances];
boolean[] isValidInstance = new boolean[numInstances];
double[] probs = null;
Instance inst;
for (int i = 0; i < numInstances; i++) {
inst = pool.instance(i);
if (inst.isMissing(desiredAttr)) {
try {
probs = myEstimator.distributionForInstance(inst);
classProb[i] = probs[(int) inst.classValue()];
isValidInstance[i] = true;
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
} else {
classProb[i] = Double.POSITIVE_INFINITY;
isValidInstance[i] = false;
}
}
double leastCorrect = classProb[Utils.minIndex(classProb)];
int numLeastCorrect = 0;
for (int i = 0; i < numInstances; i++) {
if (isValidInstance[i] && classProb[i] == leastCorrect) numLeastCorrect++;
}
int randomInstance = r.nextInt(numLeastCorrect);
int index = 0;
for (int i = 0; i < numInstances; i++) {
if (isValidInstance[i] && classProb[i] == leastCorrect) {
if (index == randomInstance) return i;
else index++;
}
}
return -1;
}
/**
* Convert a single instance over if the class is nominal. The converted instance is added to the
* end of the output queue.
*
* @param instance the instance to convert
*/
private void convertInstanceNominal(Instance instance) {
if (!m_needToTransform) {
push(instance);
return;
}
double[] vals = new double[outputFormatPeek().numAttributes()];
int attSoFar = 0;
for (int j = 0; j < getInputFormat().numAttributes(); j++) {
Attribute att = getInputFormat().attribute(j);
if ((!att.isNominal()) || (j == getInputFormat().classIndex())) {
vals[attSoFar] = instance.value(j);
attSoFar++;
} else {
if ((att.numValues() <= 2) && (!m_TransformAll)) {
vals[attSoFar] = instance.value(j);
attSoFar++;
} else {
if (instance.isMissing(j)) {
for (int k = 0; k < att.numValues(); k++) {
vals[attSoFar + k] = instance.value(j);
}
} else {
for (int k = 0; k < att.numValues(); k++) {
if (k == (int) instance.value(j)) {
vals[attSoFar + k] = 1;
} else {
vals[attSoFar + k] = 0;
}
}
}
attSoFar += att.numValues();
}
}
}
Instance inst = null;
if (instance instanceof SparseInstance) {
inst = new SparseInstance(instance.weight(), vals);
} else {
inst = new DenseInstance(instance.weight(), vals);
}
inst.setDataset(getOutputFormat());
copyValues(inst, false, instance.dataset(), getOutputFormat());
inst.setDataset(getOutputFormat());
push(inst);
}
/**
* Computes class distribution of an instance using the FastRandomTree.
*
* <p>In Weka's RandomTree, the distributions were normalized so that all probabilities sum to 1;
* this would abolish the effect of instance weights on voting. In FastRandomForest 0.97 onwards,
* the distributions are normalized by dividing with the number of instances going into a leaf.
*
* <p>
*
* @param instance the instance to compute the distribution for
* @return the computed class distribution
* @throws Exception if computation fails
*/
@Override
public double[] distributionForInstance(Instance instance) throws Exception {
double[] returnedDist = null;
if (m_Attribute > -1) { // ============================ node is not a leaf
if (instance.isMissing(m_Attribute)) { // ---------------- missing value
returnedDist = new double[m_MotherForest.getM_Info().numClasses()];
// split instance up
for (int i = 0; i < m_Successors.length; i++) {
double[] help = m_Successors[i].distributionForInstance(instance);
if (help != null) {
for (int j = 0; j < help.length; j++) {
returnedDist[j] += m_Prop[i] * help[j];
}
}
}
} else if (m_MotherForest.getM_Info().attribute(m_Attribute).isNominal()) { // ------ nominal
// returnedDist = m_Successors[(int) instance.value(m_Attribute)]
// .distributionForInstance(instance);
// 0.99: new - binary splits (also) for nominal attributes
if (instance.value(m_Attribute) == m_SplitPoint) {
returnedDist = m_Successors[0].distributionForInstance(instance);
} else {
returnedDist = m_Successors[1].distributionForInstance(instance);
}
} else { // ------------------------------------------ numeric attributes
if (instance.value(m_Attribute) < m_SplitPoint) {
returnedDist = m_Successors[0].distributionForInstance(instance);
} else {
returnedDist = m_Successors[1].distributionForInstance(instance);
}
}
return returnedDist;
} else { // =============================================== node is a leaf
return m_ClassProbs;
}
}
