BatchNormLayer.py 文件源码

def __call__(self, input): 
        mean = input.mean(self.axes, keepdims=True) 
        std = input.std(self.axes, keepdims=True) + self.epsilon 

        # Don't batchnoramlise a single data point
        mean = ifelse(T.gt(input.shape[0], 1), mean, T.zeros(mean.shape, dtype=mean.dtype))
        std  = ifelse(T.gt(input.shape[0], 1), std, T.ones(std.shape, dtype=std.dtype))

        return (input - mean) * T.addbroadcast((self.gamma / std) + self.beta, *self.axes)