data_preprocessing.py 文件源码

def _compute_global_std(self, dataset, session, limit=None):
        """ Compute std of a dataset. A limit can be specified for faster
        computation, considering only 'limit' first elements. """
        _dataset = dataset
        std = 0.
        if isinstance(limit, int):
            _dataset = _dataset[:limit]
        if isinstance(_dataset, np.ndarray) and not self.global_std_pc:
            std = np.std(_dataset)
        else:
            for i in range(len(dataset)):
                if not self.global_std_pc:
                    std += np.std(dataset[i]) / len(dataset)
                else:
                    std += (np.std(dataset[i], axis=(0, 1),
                             keepdims=True) / len(dataset))[0][0]
        self.global_std.assign(std, session)
        return std