Question

我正在尝试从OCaml中的字符串做直方图。我处于这种状态，编辑一点：create a histogram OCaml以使用字符串输入。

如何查看charFreqs的内容，或者它是否有效？

module S = String;;
module HT = Hashtbl;;

let histogram s =
    let charFreqs = HT.create 126 in
        S.iter (fun c ->
            let tmp =
                try HT.find charFreqs c
                with Not_found -> 0 in
            HT.replace charFreqs c (tmp+1)
        ) s;;

let str = "Lorem ipsum dolor sit amet, consectetur adipiscing elit.";;
let charFreqs = histogram str;;

输出：val charFreqs：unit =（）

Answer 1

您的histogram函数返回S.iter的结果，即unit：

val iter : (char -> unit) -> string -> unit

尝试类似：

let histogram s =
    let charFreqs = HT.create 126 in
        S.iter (fun c ->
            let tmp =
                try HT.find charFreqs c
                with Not_found -> 0 in
            HT.replace charFreqs c (tmp+1)
        ) s;
        charFreqs;;

Ocaml字符串直方图

1 个答案: