测试文档

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Penry
Penry
Penry
Penry

12 \sqrt{\frac{1}{2}}

Penry 魔刀千刃

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beijing

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from sklearn.decomposition import PCA

def pca_demo():
    """
    PCA降维
    :return:
    """
    data = [[2,8,4,5], [6,3,0,8], [5,4,9,1]]
    # 1、实例化一个转换器类
    transform = PCA(n_components=2)  # 4个特征降到2个特征

    # 2、调用fit_transform
    data_new = transform.fit_transform(data)
    print("data_new\n", data_new)

    transform2 = PCA(n_components=0.95)  # 保留95%的信息
    data_new2 = transform2.fit_transform(data)
    print("data_new2\n", data_new2)

    return None

if __name__ == "__main__":
    pca_demo()