F# code for computing rounding errors in STRoll

Gist.fsx

let fstroll x = (System.Math.Log2((x)/10.)*10.+10.)
let stroll x = fstroll (float x)
let roundedStroll x = (stroll x |> System.Math.Round |> int)
let round (x:float) = x |> System.Math.Round |> int
let normalize y x =
    let bigger = max y x
    let smaller = min y x
    (10. * (float bigger / float smaller))
for x in [1..25] do
    for y in [x+1..25] do
        let roundedMargin = (roundedStroll y - roundedStroll x)
        let rawMargin = (fstroll (normalize y x)) - 10.
        if round rawMargin <> roundedMargin then
            printfn $"ST {x} vs. {y}: Rounded margin %+d{ roundedMargin }. Should be %+d{ round rawMargin } (%+.2f{rawMargin})"