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How to take array of numbers and return array with numbers doubled?

I'm trying to write a function that will take an array of numbers and return an array with those numbers doubled. For example 1, 2, 3 and return should be 2, 4, 6.

This is what I have so far:

const numbers = [1, 2, 3];

function doubleNumbers(numbers) {
    return numbers =  1 * 2 + ", " + 2 * 2 + ", " + 3 * 2;
}

console.log(doubleNumbers(numbers));

This is putting out the correct answer in the console, although I have a feeling something is off.

When I change the const numbers=[1, 2, 3] to any other number, I'm still getting 2,4,6. Which leads me to believe function doubleNumbers isn't pulling the numbers from the array, only multiplying the numbers I have in return numbers.

Solution

  • You can use Array#map.

    const numbers = [1, 2, 3];

function doubleNumbers(numbers) {
    return numbers.map(x => x * 2);
}

console.log(doubleNumbers(numbers));