分类问题是使用已知类型的样本（训练集）到C。

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分类问题是利用已知类别的样品（训练集）来构造分类器，其训练集样品是已知类别的，所以又称为有监督学习。-Classification problems is the use of known types of samples (training set) to construct the classifier, its training set of known types of samples is, therefore, has also called supervised learning.