apriori_maker.py 文件源码

def apriori_alg(trans, support=0.01, minlen=2):
    print('appr_1')
    dna = trans.unstack().dropna()
    print('appr_2')
    ts = pandas.get_dummies(dna).groupby(level=1).sum()
    print('appr_3')
    collen, rowlen = ts.shape
    pattern = []
    for cnum in range(minlen, rowlen + 1):
        for cols in combinations(ts, cnum):
            print('cnum', cnum)
            patsup = ts[list(cols)].all(axis=1).sum()
            patsup = float(patsup) / collen
            pattern.append([",".join(cols), patsup])
    print('appr_4')
    sdf = pandas.DataFrame(pattern, columns=["Pattern", "Support"])
    print('appr_5')
    results = sdf[sdf.Support >= support]
    print('appr_6')
    return results

# ????????? Apriori ?? ? ??