util.py 文件源码

def cconv(a, b):
    """
    Circular convolution of vectors

    Computes the circular convolution of two vectors a and b via their
    fast fourier transforms

    a \ast b = \mathcal{F}^{-1}(\mathcal{F}(a) \odot \mathcal{F}(b))

    Parameter
    ---------
    a: real valued array (shape N)
    b: real valued array (shape N)

    Returns
    -------
    c: real valued array (shape N), representing the circular
       convolution of a and b
    """
    return ifft(fft(a) * fft(b)).real