Changeset 128 for trunk/CrossPare/src/de/ugoe/cs/cpdp/wekaclassifier/AbstractCODEP.java

Timestamp:

06/21/16 13:07:13 (8 years ago)

Author:

sherbold

Message:

• added workaround to AbstractCODEP to facilitate working with algorithms that internally use Discretize with metrics with very small value ranges. Discretize only remembers the first 5 (or 6?) diggets after the comma, if the difference is smaller it will be removed causing errors. We now added an automatic upscaling that applies if this happens for one metrics. For more metrics, the approach must be adopted.

File:

• trunk/CrossPare/src/de/ugoe/cs/cpdp/wekaclassifier/AbstractCODEP.java (modified) (5 diffs)

trunk/CrossPare/src/de/ugoe/cs/cpdp/wekaclassifier/AbstractCODEP.java

@@ -16 +16 @@
 
 import java.util.ArrayList;
+import java.util.HashMap;
 import java.util.List;
+import java.util.Map;
 import java.util.logging.Level;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
 
 import de.ugoe.cs.util.console.Console;
@@ -62 +66 @@
     private Classifier codepClassifier = null;
 
+    /**
+     * Map that store attributes for upscaling for each classifier
+     */
+    private Map<Integer, Integer> upscaleIndex = null;
+
+    /**
+     * Scaling value that moves the decimal point by 5 digets.
+     */
+    private final double SCALER = 10000.0d;
+
     /*
      * (non-Javadoc)
@@ -87 +101 @@
         setupInternalClassifiers();
         setupInternalAttributes();
-
+        upscaleIndex = new HashMap<>();
+
+        int classifierIndex = 0;
+        boolean secondAttempt = false;
+        Instances traindataCopy = null;
         for (Classifier classifier : internalClassifiers) {
-            Console.traceln(Level.FINE, "internally training " + classifier.getClass().getName());
-            classifier.buildClassifier(traindata);
+            boolean trainingSuccessfull = false;
+            do {
+                Console.traceln(Level.FINE,
+                                "internally training " + classifier.getClass().getName());
+                try {
+                    if (secondAttempt) {
+                        classifier.buildClassifier(traindataCopy);
+                        trainingSuccessfull = true;
+                    }
+                    else {
+                        classifier.buildClassifier(traindata);
+                        trainingSuccessfull = true;
+                    }
+                }
+                catch (IllegalArgumentException e) {
+                    String regex = "A nominal attribute \\((.*)\\) cannot have duplicate labels.*";
+                    Pattern p = Pattern.compile(regex);
+                    Matcher m = p.matcher(e.getMessage());
+                    if (!m.find()) {
+                        // cannot treat problem, rethrow exception
+                        throw e;
+                    }
+                    String attributeName = m.group(1);
+                    int attrIndex = traindata.attribute(attributeName).index();
+                    if (secondAttempt) {
+                        throw new RuntimeException("cannot be handled correctly yet, because upscaleIndex is a Map");
+                        // traindataCopy = upscaleAttribute(traindataCopy, attrIndex);
+                    }
+                    else {
+                        traindataCopy = upscaleAttribute(traindata, attrIndex);
+                    }
+
+                    upscaleIndex.put(classifierIndex, attrIndex);
+                    Console
+                        .traceln(Level.FINE,
+                                 "upscaled attribute " + attributeName + "; restarting training");
+                    secondAttempt = true;
+                    continue;
+                }
+            }
+            while (!trainingSuccessfull); // dummy loop for internal continue
+            classifierIndex++;
+            secondAttempt = false;
         }
 
@@ -118 +177 @@
     private Instance createInternalInstance(Instance instance) throws Exception {
         double[] values = new double[internalAttributes.size()];
+        Instances traindataCopy;
         for (int j = 0; j < internalClassifiers.size(); j++) {
+            if (upscaleIndex.containsKey(j)) {
+                // instance value must be upscaled
+                int attrIndex = upscaleIndex.get(j);
+                double upscaledVal = instance.value(attrIndex) * SCALER;
+                traindataCopy = new Instances(instance.dataset());
+                instance = new DenseInstance(instance.weight(), instance.toDoubleArray());
+                instance.setValue(attrIndex, upscaledVal);
+                traindataCopy.add(instance);
+                instance.setDataset(traindataCopy);
+            }
             values[j] = internalClassifiers.get(j).classifyInstance(instance);
         }
@@ -161 +231 @@
     /**
      * <p>
+     * Upscales the value of a single attribute. This is a workaround to get BayesNet running for
+     * all data. Works on a copy of the training data, i.e., leaves the original data untouched.
+     * </p>
+     *
+     * @param traindata
+     *            data from which the attribute is upscaled.
+     * @param attributeIndex
+     *            index of the attribute
+     * @return data with upscaled attribute
+     */
+    private Instances upscaleAttribute(Instances traindata, int attributeIndex) {
+        Instances traindataCopy = new Instances(traindata);
+        for (int i = 0; i < traindata.size(); i++) {
+            traindataCopy.get(i).setValue(attributeIndex,
+                                          traindata.get(i).value(attributeIndex) * SCALER);
+        }
+        return traindataCopy;
+    }
+
+    /**
+     * <p>
      * Abstract method through which implementing classes define which classifier is used for the
      * CODEP.