吴裕雄 python 机器学习——数据预处理过滤式特征选取SelectPercentile模型

from sklearn.feature_selection import SelectPercentile,f_classif

#数据预处理过滤式特征选取SelectPercentile模型

def test_SelectKBest():

    X=[[1,2,3,4,5],

          [5,4,3,2,1],

          [3,3,3,3,3,],

          [1,1,1,1,1]]

    y=[0,1,0,1]

    print("before transform:",X)

    selector=SelectPercentile(score_func=f_classif,percentile=10)

    selector.fit(X,y)

    print("scores_:",selector.scores_)

    print("pvalues_:",selector.pvalues_)

    print("selected index:",selector.get_support(True))

    print("after transform:",selector.transform(X))

#调用test_SelectKBest()

test_SelectKBest()