Manually calculate the square root of a number with Javascript

squirt.js

// The Babylonian Method 
// http://en.wikipedia.org/wiki/Methods_of_computing_square_roots#Babylonian_method
// @param n - the number to compute the square root of
// @param guess - the best guess so far (can omit from initial call)
function squirt(n, guess) {
    if (!guess) {
        guess = n / 2.0; // Take an initial guess at the square root
    }
    const divided = n / guess; // Divide our guess into the number
    const newGuess = (divided + guess) / 2.0; // Use average of guess and divided as our new guess
    
    if (guess == newGuess) {
        // The new guess is the same as the old guess; further guesses can get no more accurate so we return this guess
        return guess;
    }
    return squirt(n, newGuess); // Recursively solve for closer and closer approximations of the square root
}

console.log(squirt(42)); // 6.48074069840786