Error NullPointer Neuroph doOneLearningIteration

Question

我正在使用Neuroph 2.9框架编写ANN代码来预测房价。我想得到每一个错误，每次运行每个时期(以显示错误的改善在图表上)，但这导致了错误。

// create multi layer perceptron
    System.out.println("Creating neural network");
    MultiLayerPerceptron neuralNet = new MultiLayerPerceptron(
            TransferFunctionType.SIGMOID, inputsCount, hiddentsCount1,
            outputsCount);

// set learning parameters
    MomentumBackpropagation learningRule = new MomentumBackpropagation();
    learningRule.setLearningRate(0.3);
    learningRule.setMomentum(0.5);
    learningRule.setNeuralNetwork(neuralNet);

    learningRule.setTrainingSet(TrainSet);
    learningRule.doOneLearningIteration(TrainSet);

我明白了：

Exception in thread "main" java.lang.NullPointerException
at org.neuroph.nnet.learning.MomentumBackpropagation.updateNeuronWeights(MomentumBackpropagation.java:72)
at org.neuroph.nnet.learning.BackPropagation.calculateErrorAndUpdateOutputNeurons(BackPropagation.java:83)
at org.neuroph.nnet.learning.BackPropagation.updateNetworkWeights(BackPropagation.java:53)
at org.neuroph.core.learning.SupervisedLearning.learnPattern(SupervisedLearning.java:190)
at org.neuroph.core.learning.SupervisedLearning.doLearningEpoch(SupervisedLearning.java:165)
at org.neuroph.core.learning.IterativeLearning.doOneLearningIteration(IterativeLearning.java:245)
at com.thao.Main.main(Main.java:76)

问题是当我使用:learningRule.learn(TrainSet)时，它没问题，没有出现错误。文档如此糟糕，以至于不同的函数选择正确的函数来运行我想要的正确的东西。