Pull elements randomly from an array 3 by 3

Question

I have an array with list items :

var listArray = [];

$("ul li").each(function(){
    listArray.push($(this));
});

var item = listArray[Math.floor(Math.random()*listArray.length)];

item.css({
    "transform":"scale(1)"
});

and i shuffled the array as it mentioned in answers but still i am not able to pull the elements from it one by one in intervals

if you have a better idea how to do it please tell me.

DEMO : https://jsfiddle.net/rnfrxL1b/3/

There are no stupid questions, only stupid answers. Welcome to StackOverflow — Gui Imamura, Oct 05 '15 at 18:17
Taking 4 random elements is simply taking one random element four times. — Etheryte, Oct 05 '15 at 18:19
@Nit not if you don't want to take one specific element more than once. — Gui Imamura, Oct 19 '15 at 14:19
@GuiImamura Regardless of which he wants, there is a standard way to do this which one can easily search for. — Etheryte, Oct 19 '15 at 15:27

score 2 · Answer 1 · edited May 23 '17 at 11:58

2

You may first shuffle the array and then pull values from the shuffled array either one by one or 4 by 4. See shuffle method: link

edited May 23 '17 at 11:58

Community

1
1

answered Oct 05 '15 at 18:25

imnancysun

612
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14

ok i shuffled array but the problem is that i dont know how to pull elements from it 4 by 4 in intervals i have tried it with loops but without success – Oct 05 '15 at 18:47
@FrankeyWakey Did you try array slice? – imnancysun Oct 05 '15 at 20:52

score 0 · Answer 2 · edited May 23 '17 at 11:44

0

I think this is what you want: How to randomize (shuffle) a JavaScript array?

Accepted/most upvoted answer:

function shuffle(array) {
  var currentIndex = array.length, temporaryValue, randomIndex ;

  // While there remain elements to shuffle...
  while (0 !== currentIndex) {

    // Pick a remaining element...
    randomIndex = Math.floor(Math.random() * currentIndex);
    currentIndex -= 1;

    // And swap it with the current element.
    temporaryValue = array[currentIndex];
    array[currentIndex] = array[randomIndex];
    array[randomIndex] = temporaryValue;
  }

  return array;
}

Which is the Fisher-Yates (aka Knuth) Shuffle, according to the author of the answer. Please see original answer and links in it for more details.

edited May 23 '17 at 11:44

Community

1
1

answered Oct 05 '15 at 18:27

Gui Imamura

556
9
26

Yeah, I was too slow :( – Gui Imamura Oct 05 '15 at 18:31
It's the thought that counts :) – ryuu9187 Oct 05 '15 at 18:46
i used this shuffle algorythm but i still have problem to get the elements from an aray 4 by 4 in interval – Oct 05 '15 at 18:48
@FrankeyWakey please clarify that for me. So you'll have (4 * n) elements in the array, and what to get 4 random elements per iteration? – Gui Imamura Oct 06 '15 at 12:44

Pull elements randomly from an array 3 by 3

2 Answers2