R Vectors Manipulation

Sorting Vector:

Sort() function is used to sort elements of a vector

Examples:

Sorting a numeric vector

> x <- c( 20, 4, -7,6,60,0,-2)

> sort.output <- sort(x)

> sort.output

[1] -7 -2 0 4 6 20 60

Sorting above vector in reverse order

> revsort.output <- sort( x, decreasing = TRUE)

> print(revsort.output)

[1] 60 20 6 4 0 -2 -7

Sorting a character vector

> x <- c(“Amar”, “Akbar”, “Athony”)

> sort.output <- sort(x)

> print(sort.output)

[1] “Akbar” “Amar”   “Athony”

Sort above in reverse order

> revsort.output <- sort( x, decreasing = TRUE)

> print(revsort.output)

[1] “Athony” “Amar”   “Akbar”

Vector Index:

Vector Index displays a specific element of it.

> x <- c( 20, 4, -7,6,60,0,-2)

> x[4]

[1] 6

To print all element except the selected one from above vector

> x[-2]

[1] 20 -7 6 60 0 -2

Result of out – of range vector

> x[8]

[1] NA

Numeric Index Vector:

Numeric Index vector is used to slice some elements out of the vector in to a new vector

Example:

> slc <- c( 2, 4, 5, -11)

> slc[c(1,4)]

[1]   2 -11

Range Index Vector:

Range Index is used to list print a slice of element in certain range

> slc[c(2:4)]

[1]   4   5 -11

Logical Index Vector:

Logical Index Vector is used to slice elements from an existing vector of same length using its TRUE value.

> slc <- c( 2, 4, 5, -11)

> LOGIC <- c( TRUE, TRUE, TRUE, FALSE)

> slc[LOGIC]

[1] 2 4 5

Vector Arithmetic:

Same length vectors can be added, subtracted, multiplied, divided in an output

Example:

> x <- c( 2, 4, 5, -11)

> y <- c( 1, -8, 5, 30)

> add <- x+y

> print(add)

[1] 3 -4 10 19

> sub <- x-y

> print(sub)

[1]   1 12   0 -41

> mul <- x*y

> print(mul)

[1]   2 -32   25 -330

> div <- x/y

> print(div)

[1] 2.0000000 -0.5000000 1.0000000 -0.3666667