@classmethod
def like(cls, arr, eta=0):
    """Creates a new PDMA object with its shape and dtype like the specified NumPy array.

        :param arr: The array to take the shape and data type from.
        :type arr: numpy.ndarray
        :param eta: The polynomial decay factor. Must be >= 0. The default of 0 corresponds to the
            simple average. Higher values of eta correspond to a polynomially decaying window of
            degree eta.
        :type eta: float
        :returns: The new polynomial-decay moving average object.
        :rtype: average.PDMA
        """
    return cls(arr.shape, arr.dtype, eta)
