(0.1,0.4,0,0.5)
(0.1,0.4,0.1,0.5)
(0.6,0.4,0,0.5)
(0.6,0.1,0.8,-0.5)
任意一个向量,如果它内部的各个元素为非负数,且总和等于 1,则此向量称为概率向量。