Question

let highs = [| 2; 4; 6 |]
let lows = [| 1; 5; 10 |]

I want to get 2 arrays from the above: if the element in highs is smaller than the corresponding element in lows, then swap them. So, I can get the final 2 arrays:

let trueHighs = [| 2; 5; 10 |]
let trueLows = [| 1; 4; 6 |]

How do I do this?

Answer 1

Similar with JaredPar’s answer but simpler:

let trueHighs, trueLows =        
    Array.zip highs lows
    |> Array.map (fun (x, y) -> if x >= y then (x, y) else (y, x))
    |> Array.unzip

Another more concise version:

let trueHighs, trueLows =        
    (highs, lows)
    ||> Array.map2 (fun x y -> if x >= y then (x, y) else (y, x))    
    |> Array.unzip