有两种方法可以创建一个在R中具有重复值的向量，但是两种方法都有不同的方法，第一种方法是重复向量的每个元素，第二种方法将元素重复指定的次数。这两种方法都使用rep函数来创建向量。
请看以下示例-
> x1<-rep(c(1,2,3,4,5),each=10)
> x1
[1] 1 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2 2 2 2 3 3 3 3 3 3 3 3 3 3 4 4 4 4 4 4 4 4
[39] 4 4 5 5 5 5 5 5 5 5 5 5
> x2<-rep(c(1,2,3,4,5),times=10)
> x2
[1] 1 2 3 4 5 1 2 3 4 5 1 2 3 4 5 1 2 3 4 5 1 2 3 4 5 1 2 3 4 5 1 2 3 4 5 1 2 3
[39] 4 5 1 2 3 4 5 1 2 3 4 5
> x3<-rep(c(1,2,3,4,5),times=c(10,10,10,10,10))
> x3
[1] 1 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2 2 2 2 3 3 3 3 3 3 3 3 3 3 4 4 4 4 4 4 4 4
[39] 4 4 5 5 5 5 5 5 5 5 5 5
> x4<-rep(c(1,2,3,4,5),times=c(10,20,30,40,50))
> x4
[1] 1 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 3 3 3 3 3 3 3
[38] 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 4 4 4 4 4 4 4 4 4 4 4 4 4 4
[75] 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 5 5 5 5 5 5 5 5 5 5 5
[112] 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5
[149] 5 5
> x5<-rep(c(1,2,3,4,5),times=c(12,2,30,7,42))
> x5
[1] 1 1 1 1 1 1 1 1 1 1 1 1 2 2 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3
[39] 3 3 3 3 3 3 4 4 4 4 4 4 4 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5
[77] 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5
> x6<-rep(1,10)
> x6
[1] 1 1 1 1 1 1 1 1 1 1
> x7<-rep(1:5,10)
> x7
[1] 1 2 3 4 5 1 2 3 4 5 1 2 3 4 5 1 2 3 4 5 1 2 3 4 5 1 2 3 4 5 1 2 3 4 5 1 2 3
[39] 4 5 1 2 3 4 5 1 2 3 4 5
> x8<-rep(1:5,each=10)
> x8
[1] 1 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2 2 2 2 3 3 3 3 3 3 3 3 3 3 4 4 4 4 4 4 4 4
[39] 4 4 5 5 5 5 5 5 5 5 5 5
> x9<-rep(1:5,times=c(1,2,3,4,5))
> x9
[1] 1 2 2 3 3 3 4 4 4 4 5 5 5 5 5
> x10<-rep(c(letters[1:26]),times=1)
> x10
[1] "a" "b" "c" "d" "e" "f" "g" "h" "i" "j" "k" "l" "m" "n" "o" "p" "q" "r" "s"
[20] "t" "u" "v" "w" "x" "y" "z"
> x11<-rep(c(letters[1:26]),times=5)
> x11
[1] "a" "b" "c" "d" "e" "f" "g" "h" "i" "j" "k" "l" "m" "n" "o" "p" "q" "r"
[19] "s" "t" "u" "v" "w" "x" "y" "z" "a" "b" "c" "d" "e" "f" "g" "h" "i" "j"
[37] "k" "l" "m" "n" "o" "p" "q" "r" "s" "t" "u" "v" "w" "x" "y" "z" "a" "b"
[55] "c" "d" "e" "f" "g" "h" "i" "j" "k" "l" "m" "n" "o" "p" "q" "r" "s" "t"
[73] "u" "v" "w" "x" "y" "z" "a" "b" "c" "d" "e" "f" "g" "h" "i" "j" "k" "l"
[91] "m" "n" "o" "p" "q" "r" "s" "t" "u" "v" "w" "x" "y" "z" "a" "b" "c" "d"
[109] "e" "f" "g" "h" "i" "j" "k" "l" "m" "n" "o" "p" "q" "r" "s" "t" "u" "v"
[127] "w" "x" "y" "z"
> x12<-rep(c(letters[1:26]),times=1:26)
> x12
[1] "a" "b" "b" "c" "c" "c" "d" "d" "d" "d" "e" "e" "e" "e" "e" "f" "f" "f"
[19] "f" "f" "f" "g" "g" "g" "g" "g" "g" "g" "h" "h" "h" "h" "h" "h" "h" "h"
[37] "i" "i" "i" "i" "i" "i" "i" "i" "i" "j" "j" "j" "j" "j" "j" "j" "j" "j"
[55] "j" "k" "k" "k" "k" "k" "k" "k" "k" "k" "k" "k" "l" "l" "l" "l" "l" "l"
[73] "l" "l" "l" "l" "l" "l" "m" "m" "m" "m" "m" "m" "m" "m" "m" "m" "m" "m"
[91] "m" "n" "n" "n" "n" "n" "n" "n" "n" "n" "n" "n" "n" "n" "n" "o" "o" "o"
[109] "o" "o" "o" "o" "o" "o" "o" "o" "o" "o" "o" "o" "p" "p" "p" "p" "p" "p"
[127] "p" "p" "p" "p" "p" "p" "p" "p" "p" "p" "q" "q" "q" "q" "q" "q" "q" "q"
[145] "q" "q" "q" "q" "q" "q" "q" "q" "q" "r" "r" "r" "r" "r" "r" "r" "r" "r"
[163] "r" "r" "r" "r" "r" "r" "r" "r" "r" "s" "s" "s" "s" "s" "s" "s" "s" "s"
[181] "s" "s" "s" "s" "s" "s" "s" "s" "s" "s" "t" "t" "t" "t" "t" "t" "t" "t"
[199] "t" "t" "t" "t" "t" "t" "t" "t" "t" "t" "t" "t" "u" "u" "u" "u" "u" "u"
[217] "u" "u" "u" "u" "u" "u" "u" "u" "u" "u" "u" "u" "u" "u" "u" "v" "v" "v"
[235] "v" "v" "v" "v" "v" "v" "v" "v" "v" "v" "v" "v" "v" "v" "v" "v" "v" "v"
[253] "v" "w" "w" "w" "w" "w" "w" "w" "w" "w" "w" "w" "w" "w" "w" "w" "w" "w"
[271] "w" "w" "w" "w" "w" "w" "x" "x" "x" "x" "x" "x" "x" "x" "x" "x" "x" "x"
[289] "x" "x" "x" "x" "x" "x" "x" "x" "x" "x" "x" "x" "y" "y" "y" "y" "y" "y"
[307] "y" "y" "y" "y" "y" "y" "y" "y" "y" "y" "y" "y" "y" "y" "y" "y" "y" "y"
[325] "y" "z" "z" "z" "z" "z" "z" "z" "z" "z" "z" "z" "z" "z" "z" "z" "z" "z"
[343] "z" "z" "z" "z" "z" "z" "z" "z" "z"
> x13<-rep(c("A","B","C","D"),times=c(4,3,2,1))
> x13
[1] "A" "A" "A" "A" "B" "B" "B" "C" "C" "D"