How to sum an array of numbers using reduce()
Swift version: 5.2
The reduce() method is designed to convert a sequence into a single value, which makes it perfect for calculating the total of an array of numbers.
For example, given the following number array:
let numbers = [1, 12, 2, 9, 27]We could calculate the total of all those numbers like this:
let total = numbers.reduce(0, +)The first parameter passed to reduce() is the value it should start with, in this case 0. The second parameter is how it should combine that 0 with each item in your array, which means it will do 0 + 1 to make 1, then 1 + 12 to make 13, and so on.
SPONSORED Announcing NSSpain 2020: Remote Edition! An online, continuous conference for iOS developers. We’ll start on Thursday and finish on Friday, with talks, activities, and lots of fun for 36 hours, non-stop. Sound good? Join us!
Sponsor Hacking with Swift and reach the world's largest Swift community!
Available from iOS 8.0
Similar solutions…
- How to create views in a loop using ForEach
- What is a monad?
- How to convert dates and times to a string using DateFormatter
- How to position views in a grid using LazyVGrid and LazyHGrid
- How to sort an array using sort()
About the Swift Knowledge Base
This is part of the Swift Knowledge Base, a free, searchable collection of solutions for common iOS questions.
