Round currency closest to five

Question

I\'d like to round my values to the closest of 5 cent for example:

5.31 -> 5.30
5.35 -> 5.35
5.33 -> 5.35
5.38 -> 5.40

Currentl

Answer 1

It's really better to stay away from floating-point for this kind of thing, but you can probably improve the accuracy a little with this:

import Foundation

func roundToFive(n: Double) -> Double {
  let f = floor(n)
  return f + round((n-f) * 20) / 20
}

roundToFive(12.12) // 12.1