NN Cost Function

cost.py

class Trainer(object):
    def __init__(self, nn, data, label):
        self.nn = nn
        self.data = data
        self.label = label

    def __call__(self, weights):
        from pybrain.utilities import percentError
        self.nn._setParameters(weights)
        output = self.nn.activateOnDataset(self.data)
        return percentError(output, self.label)