graphics.py 文件源码

def __nearest_pow_2(self,x):
        """
        Find power of two nearest to x
        >>> _nearest_pow_2(3)
        2.0
        >>> _nearest_pow_2(15)
        16.0
        :type x: float
        :param x: Number
        :rtype: Int
        :return: Nearest power of 2 to x
        """
        a = math.pow(2, math.ceil(np.log2(x)))
        b = math.pow(2, math.floor(np.log2(x)))
        if abs(a - x) < abs(b - x):
            return a
        else:
            return b

    # calculate spectrogram of signals