LDA降维是常用的降维手段之一，是常用的有监督学习降维工具。这个文件对其产生W后的使用进行了简要说明，使用W进行最终的降维可以得到十分漂亮的分析结果（在数据分布符合假设分析的情况下。）(LDA dimension reduction is one of the commonly used dimensionality reduction methods. It is a commonly used supervised learning dimensionality reduction tool. This file gives a brief descr iption of the use of W after it was generated, and the final dimensionality reduction using W yields a very nice analysis result (if the data distribution conforms to the hypothetical analysis).)