BUG REPORT - MetaCost with Linear Discriminant Analysis operator does not work

The MetaCost operator fails to run when the Linear Discriminant Analysis operator is used as the base learner.

The following Stack Trace is generated in the Debug Mode:

• Exception: java.lang.NullPointerException
• Message: null
• Stack trace:
• com.rapidminer.example.table.DataRow.set(DataRow.java:84)
• com.rapidminer.belt.table.ConvertOnWriteExampleTable$1$1.set(ConvertOnWriteExampleTable.java:188)
• com.rapidminer.example.table.AbstractAttribute.setValue(AbstractAttribute.java:192)
• com.rapidminer.example.table.DataRow.set(DataRow.java:84)
• com.rapidminer.example.Example.setValue(Example.java:142)
• com.rapidminer.example.Example.setConfidence(Example.java:214)
• com.rapidminer.operator.learner.meta.MetaCostModel.performPrediction(MetaCostModel.java:156)
• com.rapidminer.operator.learner.PredictionModel.apply(PredictionModel.java:117)
• com.rapidminer.operator.AbstractModel.apply(AbstractModel.java:82)
• com.rapidminer.operator.AbstractModel.apply(AbstractModel.java:34)
• com.rapidminer.operator.ModelApplier.applyModel(ModelApplier.java:140)
• com.rapidminer.operator.ModelApplier.doWork(ModelApplier.java:125)
• com.rapidminer.operator.Operator.execute(Operator.java:1023)
• com.rapidminer.operator.execution.SimpleUnitExecutor.execute(SimpleUnitExecutor.java:77)
• com.rapidminer.operator.ExecutionUnit$2.run(ExecutionUnit.java:805)
• com.rapidminer.operator.ExecutionUnit$2.run(ExecutionUnit.java:800)
• java.security.AccessController.doPrivileged(Native Method)
• com.rapidminer.operator.ExecutionUnit.execute(ExecutionUnit.java:800)
• com.rapidminer.operator.OperatorChain.doWork(OperatorChain.java:423)
• com.rapidminer.operator.Operator.execute(Operator.java:1023)
• com.rapidminer.Process.executeRoot(Process.java:1464)
• com.rapidminer.Process.lambda$executeRootInPool$5(Process.java:1443)
• com.rapidminer.studio.concurrency.internal.AbstractConcurrencyContext$AdaptedCallable.exec(AbstractConcurrencyContext.java:362)
• java.util.concurrent.ForkJoinTask.doExec(ForkJoinTask.java:289)
• java.util.concurrent.ForkJoinPool$WorkQueue.runTask(ForkJoinPool.java:1056)
• java.util.concurrent.ForkJoinPool.runWorker(ForkJoinPool.java:1692)
• java.util.concurrent.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:175)