Data Management : Repeats in R Languages

Repeats

• Command rep is used to replicates the values in a vector.
• Syntax rep (x) replicates the values in a vector x.
• rep (x, times=n )  # Repeat x as a whole n times
• rep (x, each=n )  # Repeat each cell n times

Help for the command rep

> help  ("rep")

rep { base }

      Replicate Element of Vectors and Lists

Description

rep replicates the values in x. It is generic function, and the (internal) default method is described here.
rep.int and rep-len are faster simplified versions for two common cases.
They are not generic.

Usage

rep (x, ......)
rep.int (x,  times)
rep_len (x, length.out)

The command rep

Repeat an object n-times:

> rep (3.5,  times = 10)

[1]     3.5    3.5    3.5   3.5    3.5    3.5   3.5    3.5    3.5     3.5

> rep ( 1 :4,  2)
   [1]   1   2    3    4     1    2    3    4

Repeat an object n-times

rep (x, times  = n)

Repeat each cell n-times:

rep (x, each = n)

> x <- 1 : 3
> x
 [1]   1  2  3

>  rep (x,  times = 3)
  [1]  1   2   3  1    2   3   1   2   3

> rep (x, each = 3 )
   [1]  1    1   1    2    2   2   3     3    3

Every object is repeated several times successively:

> rep (1 : 4,   each  =  2)
   [1]   1    1   2   2   3   3   4   4

> rep ( 1 : 4,  each = 2 ,  times = 3)
 [1]   1  1   2   2    3    3   4   4   1   1   2   2    3   3   4   4   1   1   2   2    3    3   4    4

Every object is repeated a different number of times:

> rep  (1 : 4,  2 :  5)
  [1]   1   1   2   2    2    3    3   3   3   4    4    4   4    4