What are R Recursive Functions?

A recursive function in R is a function that calls itself in order to solve a problem. Recursion is a powerful concept in programming, especially useful for problems that can be broken down into smaller, similar sub-problems, such as calculating factorials, generating Fibonacci sequences, or traversing hierarchical data structures.

# Example of a recursive function to calculate factorial
factorial <- function(n) {
    if (n == 1) {
        return(1)
    } else {
        return(n * factorial(n - 1))
    }
}

# Calculate the factorial of 5
result <- factorial(5)
print(result)  # Output: 120

In this example, the factorial function calculates the factorial of a number n by calling itself with n - 1 until it reaches the base case, where n is 1. The result is the product of all integers from 1 to n.

Recursive functions can simplify complex problems by breaking them down into more manageable sub-problems. However, it’s important to ensure that the recursion has a base case to prevent infinite recursion, which could lead to a stack overflow error.