10.5 Gradient_Classifier.py 文件源码

 复制代码def test_GradientBoostingClassifier_maxdepth(*data):
    '''
    test the performance with different max_depth
    :param data:     train_data, test_data, train_value, test_value
    :return:  None
    '''
    X_train,X_test,y_train,y_test=data
    maxdepths=np.arange(1,20)
    fig=plt.figure()
    ax=fig.add_subplot(1,1,1)
    testing_scores=[]
    training_scores=[]
    for maxdepth in maxdepths:
        clf=ensemble.GradientBoostingClassifier(max_depth=maxdepth,max_leaf_nodes=None)
        clf.fit(X_train,y_train)
        training_scores.append(clf.score(X_train,y_train))
        testing_scores.append(clf.score(X_test,y_test))
    ax.plot(maxdepths,training_scores,label="Training Score")
    ax.plot(maxdepths,testing_scores,label="Testing Score")
    ax.set_xlabel("max_depth")
    ax.set_ylabel("score")
    ax.legend(loc="lower right")
    ax.set_ylim(0,1.05)
    plt.suptitle("GradientBoostingClassifier")
    plt.show()