Perform the following steps to create and see vector in R:

> x=c(1,2,3,4) # c(1:4) 
> x 
Output: 
[1] 1 2 3 4 
> x=c(1,2,3,4,"ABC") 
> x 
Output: 
[1] "1" "2" "3" "4" "ABC" 
> x * 2 
Output: 
[1] 2 4 6 8 
> sqrt(x) 
Output: 
[1] 1.000000 1.414214 1.732051 2.000000 
> y = x==2 
> y 
Output: 
[1] FALSE TRUE FALSE FALSE 
> class(y) 
Output: 
[1] "logical" 
> t = c(1:10) 
> t 
Output: 
[1] 1 2 3 4 5 6 7 8 9 10

Printing a vector will starts with index [1] which shows the elements are indexed in vector and it starts from 1, not from 0 like other languages. Any operation done on a vector is applied on individual elements of the vector, so the multiplication operation is applied on individual elements of the vector. If vector is passed as an argument to any inbuilt function, it will be applied on individual elements. You can see how powerful it is and it removes the need to write the loops for doing the operation. The vector changes the type on basis of data it holds and operation we apply on it. Using x==2 will check each element of vector for equality with two and returns the vector with logical value, that is, TRUE or FALSE. There are many other ways of creating a vector; one such way is shown in creating vector t.

Perform the following steps to create and see a list in R:

> y = list(1,2,3,"ABC") 
> y 
Output: 
[[1]]
[1]1
[[2]]
[1]2
[[3]]
[1]3
[[4]]
[1] "ABC" 
> y = list(c(1,2,3),c("A","B","C")) 
> y 
Output: 
[[1]]
[1] 1 2 3
[[2]]
[1] "A" "B" "C"

A list, as said, can contain anything; we start with a simple example to store some elements in a list using the list function. In the next step, we create a list with a vector as element of the list. So, y is a list with its first element as vector of 1, 2, 3 and its second element as vector of A, B, and C.

Perform the following steps to create and see an array in R:

> t = array(c(1,2,3,4), dim=c(2,2)) # Create two dimensional array 
> t 
Output: 
    [,1]       [,2]
[1,] 1          3
[2,] 2          4 
> arr = array(c(1:24), dim=c(3,4,2)) # Creating three dimensional array 
> arr 
Output: 
, , 1   

      [,1] [,2] [,3] [,4]
[1,]    1    4    7   10
[2,]    2    5    8   11
[3,]    3    6    9   12
, , 2 
      [,1] [,2] [,3] [,4]
[1,]   13   16   19   22
[2,]   14   17   20   23 
[3,]   15   18   21   24 

Creating an array is straightforward. Use the array function and provide the value for n^th row; it will create a two-dimensional array with appropriate columns.

Perform the following steps to create and see a matrix in R:

> m = matrix(c(1,2,3,4,5,6), nrow=3) 
> m 
Output: 
[,1]       [,2]
[1,] 1      4
[2,] 2      5
[3,] 3      6