randtest.py 文件源码

def spectraltest(binin):
    '''The focus of this test is the peak heights in the discrete Fast Fourier Transform. The purpose of this test is to detect periodic features (i.e., repetitive patterns that are near each other) in the tested sequence that would indicate a deviation from the assumption of randomness. '''

    n = len(binin)
    ss = [int(el) for el in binin]
    sc = map(sumi, ss)
    ft = sff.fft(sc)
    af = abs(ft)[1:n/2+1:]
    t = np.sqrt(np.log(1/0.05)*n)
    n0 = 0.95*n/2
    n1 = len(np.where(af<t)[0])
    d = (n1 - n0)/np.sqrt(n*0.95*0.05/4)
    pval = spc.erfc(abs(d)/np.sqrt(2))
    return pval > 0.01