交叉验证 - 类型错误：只有长度为 1 的数组才能转换为 Python 标量

Question

我试图使用CrossValidator对我的数据执行交叉验证任务。但是，它不起作用，而是给了我以下错误：

Traceback (most recent call last):
  File "/home/sfalk/workspace/SemEval2016/java/semeval2016-python/semeval_slot1_pybrain_cv.py", line 173, in <module>
    evaluation = ModuleValidator.classificationPerformance(trainer.module, ds)
  File "/usr/local/lib/python2.7/dist-packages/pybrain/tools/validation.py", line 168, in classificationPerformance
    dataset)
  File "/usr/local/lib/python2.7/dist-packages/pybrain/tools/validation.py", line 204, in validate
    return valfunc(output, target)
  File "/usr/local/lib/python2.7/dist-packages/pybrain/tools/validation.py", line 33, in classificationPerformance
    return float(n_correct) / float(len(output))
TypeError: only length-1 arrays can be converted to Python scalars

代码：

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有什么建议说问题就在这里？在