Fisher判别适合于两类的判别分析。本文采用的鸢尾花数据库中鸢尾花类别有三类，所以先采用Fisher判别对数据进行二分类判别分析，然后采用一对一进行多分类。(Fisher discriminant analysis is suitable for two kinds of discriminant analysis. There are three categories of iris in the iris database in this paper, so the Fisher disc