R PROGRAMMING

Question 1

Sorting

Answer 1

The function sort, sorts
a vector in increasing order.

Question 2

Order

Answer 2

It takes vectors as input, and returns the vector of indexes that sorts the input vector.

Question 3

example for order

Answer 3

ind <- order(murders$total)
# This gives the index of total murder in increasing order
murders$abb[ind]

Question 4

Example For order

Answer 4

x <- c(5,4,6,3,1,0)
index <- order(x)
x[index]

output
ans: 0 1 3 4 5 6

Question 5

MAX

Answer 5

If we are only interested in the value, we can use max function

Question 6

Which.Max

Answer 6

If we want the index, we use which.max function

Question 7

RANK

Answer 7

For any given vector it returns a vector with the rank of the first
entry, second entry, etc., of the input vecto

Question 8

Which.max example

Answer 8

i_max <- which.max(murders$total)
murders$state[i_max]
#> [1] “California”

Question 9

HOW TO REORDER USING ORDER FUNCTION

Answer 9

STEP 1 : FIND THE INDEX AT WHICH THE VECTORS ARE SORTED.
STEP 2: REORDER THE OBJECT USING ASSIGNED OBJECT INSIDE THE SQUARE BRACKET []

Question 10

TAKE input from the user

Answer 10

When we are working with R in an interactive session, we can use readline() function to take input from the user (terminal)

Question 11

TAKE input from the user EXAMPLE

Answer 11

my.name <- readline(prompt=”Enter name: “)
my.age <- readline(prompt=”Enter age: “)
# convert character into integer
my.age <- as.integer(my.age)
print(paste(“Hi,”, my.name, “next year you will be”, my.age+1, “years old.”))