data(iris)
iris
names(iris)
iris[[1]]>mean(iris[[1]])
pairlist(a=1,b='foo',c=1:5)
sqrt(36)
rnorm(10)
n = c(2, 3, 5) 
s = c("aa", "bb", "cc") 
b = c(TRUE, FALSE, TRUE) 
df = data.frame(n, s, b)
