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The Waikato Environment for Knowledge Analysis (WEKA), a machine
learning workbench. This version represents the developer version, the
"bleeding edge" of development, you could say. New functionality gets added
to this version.
/*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see m_dataLegend;
/** Actual data point values */
protected double[] m_dataPoint;
/** Re-usable chart data */
protected Data m_chartData = new Data(StepManager.CON_CHART);
protected double m_min = Double.MAX_VALUE;
protected double m_max = Double.MIN_VALUE;
/** how often (in milliseconds) to report throughput to the log */
protected int m_statusFrequency = 2000;
/** Count of instances seen */
protected int m_instanceCount;
// output info retrieval and auc stats for each class (if class is nominal)
protected boolean m_outputInfoRetrievalStats;
/** Main eval object */
protected Evaluation m_eval;
/**
* window size for computing performance metrics - 0 means no window, i.e
* don't "forget" performance on any instances
*/
protected int m_windowSize;
/** Evaluation object for window */
protected Evaluation m_windowEval;
/** Window instances */
protected LinkedList m_window;
/** Window predictions */
protected LinkedList m_windowedPreds;
/** True if rest */
protected boolean m_reset;
/** Holds the name of the classifier being used */
protected String m_classifierName;
/**
* Initialize the step.
*
* @throws WekaException if a problem occurs during initialization
*/
@Override
public void stepInit() throws WekaException {
m_instanceCount = 0;
m_dataPoint = new double[1];
m_dataLegend = new ArrayList();
if (m_windowSize > 0) {
m_window = new LinkedList();
m_windowedPreds = new LinkedList();
getStepManager().logBasic(
"Chart output using windowed " + "evaluation over " + m_windowSize
+ " instances");
}
m_reset = true;
}
/**
* Get a list of incoming connection types that this step can accept. Ideally
* (and if appropriate), this should take into account the state of the step
* and any existing incoming connections. E.g. a step might be able to accept
* one (and only one) incoming batch data connection.
*
* @return a list of incoming connections that this step can accept given its
* current state
*/
@Override
public List getIncomingConnectionTypes() {
if (getStepManager().numIncomingConnections() == 0) {
return Arrays.asList(StepManager.CON_INCREMENTAL_CLASSIFIER);
}
return new ArrayList();
}
/**
* Get a list of outgoing connection types that this step can produce. Ideally
* (and if appropriate), this should take into account the state of the step
* and the incoming connections. E.g. depending on what incoming connection is
* present, a step might be able to produce a trainingSet output, a testSet
* output or neither, but not both.
*
* @return a list of outgoing connections that this step can produce
*/
@Override
public List getOutgoingConnectionTypes() {
List result = new ArrayList();
if (getStepManager().numIncomingConnectionsOfType(
StepManager.CON_INCREMENTAL_CLASSIFIER) > 0) {
result.add(StepManager.CON_TEXT);
result.add(StepManager.CON_CHART);
}
return result;
}
/**
* Process an incoming data payload (if the step accepts incoming connections)
*
* @param data the payload to process
* @throws WekaException if a problem occurs
*/
@Override
public void processIncoming(Data data) throws WekaException {
if (isStopRequested()) {
return;
}
if (getStepManager().isStreamFinished(data)) {
// done
// notify downstream steps of end of stream
Data d = new Data(StepManager.CON_CHART);
getStepManager().throughputFinished(d);
// save memory if using windowed evaluation
m_windowEval = null;
m_window = null;
m_windowedPreds = null;
if (getStepManager().numOutgoingConnectionsOfType(StepManager.CON_TEXT) > 0) {
try {
String textTitle = m_classifierName;
String results =
"=== Performance information ===\n\n" + "Scheme: " + textTitle
+ "\n" + "Relation: " + m_eval.getHeader().relationName()
+ "\n\n" + m_eval.toSummaryString();
if (m_eval.getHeader().classIndex() >= 0
&& m_eval.getHeader().classAttribute().isNominal()
&& (m_outputInfoRetrievalStats)) {
results += "\n" + m_eval.toClassDetailsString();
}
if (m_eval.getHeader().classIndex() >= 0
&& m_eval.getHeader().classAttribute().isNominal()) {
results += "\n" + m_eval.toMatrixString();
}
textTitle = "Results: " + textTitle;
Data textData = new Data(StepManager.CON_TEXT);
textData.setPayloadElement(StepManager.CON_TEXT, results);
textData.setPayloadElement(StepManager.CON_AUX_DATA_TEXT_TITLE,
textTitle);
getStepManager().outputData(textData);
} catch (Exception ex) {
throw new WekaException(ex);
}
}
return;
}
weka.classifiers.Classifier classifier =
(weka.classifiers.Classifier) data
.getPayloadElement(StepManager.CON_INCREMENTAL_CLASSIFIER);
Instance instance =
(Instance) data.getPayloadElement(StepManager.CON_AUX_DATA_TEST_INSTANCE);
try {
if (m_reset) {
m_reset = false;
m_classifierName = classifier.getClass().getName();
m_classifierName =
m_classifierName.substring(m_classifierName.lastIndexOf(".") + 1,
m_classifierName.length());
m_eval = new Evaluation(instance.dataset());
m_eval.useNoPriors();
if (m_windowSize > 0) {
m_windowEval = new Evaluation(instance.dataset());
m_windowEval.useNoPriors();
}
if (instance.classAttribute().isNominal()) {
if (!instance.classIsMissing()) {
m_dataPoint = new double[3];
m_dataLegend.add("Accuracy");
m_dataLegend.add("RMSE (prob)");
m_dataLegend.add("Kappa");
} else {
m_dataPoint = new double[1];
m_dataLegend.add("Confidence");
}
} else {
m_dataPoint = new double[1];
if (instance.classIsMissing()) {
m_dataLegend.add("Prediction");
} else {
m_dataLegend.add("RMSE");
}
}
}
getStepManager().throughputUpdateStart();
m_instanceCount++;
double[] dist = classifier.distributionForInstance(instance);
double pred = 0;
if (!instance.classIsMissing()) {
if (m_outputInfoRetrievalStats) {
m_eval.evaluateModelOnceAndRecordPrediction(dist, instance);
} else {
m_eval.evaluateModelOnce(dist, instance);
}
if (m_windowSize > 0) {
m_windowEval.evaluateModelOnce(dist, instance);
m_window.addFirst(instance);
m_windowedPreds.addFirst(dist);
if (m_instanceCount > m_windowSize) {
// forget the oldest prediction
Instance oldest = m_window.removeLast();
double[] oldDist = m_windowedPreds.removeLast();
oldest.setWeight(-oldest.weight());
m_windowEval.evaluateModelOnce(oldDist, oldest);
oldest.setWeight(-oldest.weight());
}
}
} else {
pred = classifier.classifyInstance(instance);
}
if (instance.classIndex() >= 0) {
// need to check that the class is not missing
if (instance.classAttribute().isNominal()) {
if (!instance.classIsMissing()) {
if (m_windowSize > 0) {
m_dataPoint[1] = m_windowEval.rootMeanSquaredError();
m_dataPoint[2] = m_windowEval.kappa();
} else {
m_dataPoint[1] = m_eval.rootMeanSquaredError();
m_dataPoint[2] = m_eval.kappa();
}
}
double primaryMeasure = 0;
if (!instance.classIsMissing()) {
primaryMeasure =
m_windowSize > 0 ? 1.0 - m_windowEval.errorRate() : 1.0 - m_eval
.errorRate();
} else {
// record confidence as the primary measure
// (another possibility would be entropy of
// the distribution, or perhaps average
// confidence)
primaryMeasure = dist[Utils.maxIndex(dist)];
}
m_dataPoint[0] = primaryMeasure;
m_chartData
.setPayloadElement(StepManager.CON_AUX_DATA_CHART_MIN, 0.0);
m_chartData
.setPayloadElement(StepManager.CON_AUX_DATA_CHART_MAX, 1.0);
m_chartData.setPayloadElement(StepManager.CON_AUX_DATA_CHART_LEGEND,
m_dataLegend);
m_chartData.setPayloadElement(
StepManager.CON_AUX_DATA_CHART_DATA_POINT, m_dataPoint);
} else {
// numeric class
double update;
if (!instance.classIsMissing()) {
update =
m_windowSize > 0 ? m_windowEval.rootMeanSquaredError() : m_eval
.rootMeanSquaredError();
} else {
update = pred;
}
m_dataPoint[0] = update;
if (update > m_max) {
m_max = update;
}
if (update < m_min) {
m_min = update;
}
m_chartData.setPayloadElement(StepManager.CON_AUX_DATA_CHART_MIN,
instance.classIsMissing() ? m_min : 0.0);
m_chartData.setPayloadElement(StepManager.CON_AUX_DATA_CHART_MAX,
m_max);
m_chartData.setPayloadElement(StepManager.CON_AUX_DATA_CHART_LEGEND,
m_dataLegend);
m_chartData.setPayloadElement(
StepManager.CON_AUX_DATA_CHART_DATA_POINT, m_dataPoint);
}
if (isStopRequested()) {
return;
}
getStepManager().throughputUpdateEnd();
getStepManager().outputData(m_chartData.getConnectionName(),
m_chartData);
}
} catch (Exception ex) {
throw new WekaException(ex);
}
}
/**
* Set how often progress is reported to the status bar.
*
* @param s report progress every s instances
*/
public void setStatusFrequency(int s) {
m_statusFrequency = s;
}
/**
* Get how often progress is reported to the status bar.
*
* @return after how many instances, progress is reported to the status bar
*/
public int getStatusFrequency() {
return m_statusFrequency;
}
/**
* Return a tip text string for this property
*
* @return a string for the tip text
*/
public String statusFrequencyTipText() {
return "How often to report progress to the status bar.";
}
/**
* Set whether to output per-class information retrieval statistics (nominal
* class only).
*
* @param i true if info retrieval stats are to be output
*/
public void setOutputPerClassInfoRetrievalStats(boolean i) {
m_outputInfoRetrievalStats = i;
}
/**
* Get whether per-class information retrieval stats are to be output.
*
* @return true if info retrieval stats are to be output
*/
public boolean getOutputPerClassInfoRetrievalStats() {
return m_outputInfoRetrievalStats;
}
/**
* Return a tip text string for this property
*
* @return a string for the tip text
*/
public String outputPerClassInfoRetrievalStatsTipText() {
return "Output per-class info retrieval stats. If set to true, predictions get "
+ "stored so that stats such as AUC can be computed. Note: this consumes some memory.";
}
/**
* Set whether to compute evaluation for charting over a fixed sized window of
* the most recent instances (rather than the whole stream).
*
* @param windowSize the size of the window to use for computing the
* evaluation metrics used for charting. Setting a value of zero or
* less specifies that no windowing is to be used.
*/
public void setChartingEvalWindowSize(int windowSize) {
m_windowSize = windowSize;
}
/**
* Get whether to compute evaluation for charting over a fixed sized window of
* the most recent instances (rather than the whole stream).
*
* @return the size of the window to use for computing the evaluation metrics
* used for charting. Setting a value of zero or less specifies that
* no windowing is to be used.
*/
public int getChartingEvalWindowSize() {
return m_windowSize;
}
/**
* Return a tip text string for this property
*
* @return a string for the tip text
*/
public String chartingEvalWindowSizeTipText() {
return "For charting only, specify a sliding window size over which to compute "
+ "performance stats. <= 0 means eval on whole stream";
}
}
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