test/rndTest.ml @@ -1,4 +1,37 @@ -let dichotomic_walk_seq arr = - let len = Array.length arr in - let s = Seq.dichotomy_int 0 len in - Seq.map (fun idx -> arr.(idx)) (Seq.push_front 0 s) +module Shuffle = struct + + type 'a t = { + values: 'a array; + mutable pos: int; + } + + let create values = { + values = Array.copy values; + pos = 0; + } + + let _shuffle sh = + let len = Array.length sh.values in + if sh.pos < len + then + begin + let idx = Random.int (len - sh.pos) in + let tmp = sh.values.(sh.pos + idx) in + sh.values.(sh.pos + idx) <- sh.values.(sh.pos); + sh.values.(sh.pos) <- tmp; + sh.pos <- sh.pos + 1; + sh + end + else + failwith "index error" + + let rec get sh idx = + if idx < sh.pos + then + sh.values.(idx) + else + get (_shuffle sh) idx + +end (* module Shuffle *) + + rnd.ml 9f42c423a57c45be0951b0fdbb8bd2781b71bb54 Ludovic Coquelle lcoquelle@gmail.com http://github.com/khigia/ocaml-anneal/commit/b6694fa23d81626079c0de2e2fa30a4147248582 b6694fa23d81626079c0de2e2fa30a4147248582 2008-06-17T18:10:33-07:00 2008-06-17T18:10:33-07:00 Added Rnd.Shuffle: shuffle with random access (based on array) and lazy property: shuffle only elements if accessed (not using Lazy to provide easy random access). 1c48ce0a434fa7cb3c63fbdc51850af9e07515af Ludovic Coquelle lcoquelle@gmail.com