Loops in R

In this tutorial, we will learn about different types of loops in R. We will cover the basics of for, while, and repeat loops.

What is a Loop

A loop is a control flow statement that allows code to be executed repeatedly based on a condition.

Loops

R supports three types of loops: for loops, while loops, and repeat loops.

For Loop

A for loop is used when the number of iterations is known before entering the loop. The syntax for the for loop is:

for (variable in sequence) {
    # Code block to be executed
}

While Loop

A while loop is used when the number of iterations is not known beforehand. The syntax for the while loop is:

while (condition) {
    # Code block to be executed
}

Repeat Loop

A repeat loop is used to execute a code block repeatedly until a condition is met. The syntax for the repeat loop is:

repeat {
    # Code block to be executed
    if (condition) {
        break
    }
}

Example 1: Printing Numbers from 1 to 10 using For Loop

  1. Use a for loop to print numbers from 1 to 10.

R Program

for (i in 1:10) {
    cat(i, ' ')
}

Output

1 2 3 4 5 6 7 8 9 10

Example 2: Printing Numbers from 1 to 5 using While Loop

  1. Declare an integer variable i and initialize it to 1.
  2. Use a while loop to print numbers from 1 to 5.

R Program

i <- 1
while (i <= 5) {
    cat(i, ' ')
    i <- i + 1
}

Output

1 2 3 4 5

Example 3: Printing Numbers from 1 to 3 using Repeat Loop

  1. Declare an integer variable i and initialize it to 1.
  2. Use a repeat loop to print numbers from 1 to 3.

R Program

i <- 1
repeat {
    cat(i, ' ')
    i <- i + 1
    if (i > 3) {
        break
    }
}

Output

1 2 3