test 

a<-matrix(11:30,ncol = 2)
a
colnames(a)<-LETTERS[1:2]
a
plot(a,col="red")

rnorm(10,mean = 20 , sd = 3)
round(rnorm(10,mean = 20 , sd = 3),1)

LETTERS[1:27]

　　

 

posted @ 2020-02-14 21:18  ispenser  阅读(62)  评论(0)    收藏  举报