prettyPrintf.fsx

let inline prettyPrint (row : int ) (space : string) (lst: 'a list) =

    let swapRowColumn lst =
        lst
        |> List.collect List.indexed
        |> List.groupBy fst
        |> List.map snd
        |> List.map (List.map snd)

    let sjis = System.Text.Encoding.GetEncoding "Shift_JIS"

    let justify lst  =
        let lst = lst|> List.map ( fun x -> string x , sjis.GetByteCount (string x) )
        let max =
            lst
            |> List.map snd
            |> List.max
        List.map (fun (str, len) -> str + String.replicate (max - len) " ") lst

    lst
    |> List.chunkBySize row
    |> swapRowColumn
    |> List.map justify
    |> List.map ( List.reduce ( fun a b -> a + space +  b ))
    |> List.iter ( fun l -> printfn "%s" l )

['a'..'z'] |> prettyPrint 3 "\t"

a	d	g	j	m	p	s	v	y
b	e	h	k	n	q	t	w	z
c	f	i	l	o	r	u	x

.

[1..30] |> prettyPrint 3 "\t"

1 	4 	7 	10	13	16	19	22	25	28
2 	5 	8 	11	14	17	20	23	26	29
3 	6 	9 	12	15	18	21	24	27	30