I’m afraid I may not have fully understood your question. I think you’re asking how to use your randomsort() function when it’s declared as the method of a custom class. If so, you need to create an instance of this class, then reference the class’s method. If this class is named CustomClass, for example, you would do this:

var cc:CustomClass = new CustomClass();
this_array.sort(cc.randomsort);

this_array.sort(randomsort);

and later in the class:

function randomrange(minval, maxval) {
return minval + Math.floor(Math.random() * (maxval + 1 - minval)); }

function randomsort() {
//pass a function to sort makes it the sort criteria.. in this case just shuffle..
var t = randomrange(-1, 1);
return t
}

That sounds like you’re looping through the array until equal to its length rather than less than its length.

I’ve a problem with the randomize move from label to label . My need is the same that the Brian (february 10th) but with 49 elements in the Array. “My” function is equal to that your reply to Brian’s question, except by the number of elements (frame labels).

Everything in function works perfectly, until in 25th execution of getRandomLabel. In that moment the functions trace show in the list a “undefined” result. The trace of labels.length correctly shows the amount to it of elements of the Array.

Can you help me with some possible solution for my problem?
Your blog has been helpful in my learning.

Thank you very much.

Marcos Paim

Thanks for turning that one up again! I knew that was out there, but hadn’t been able to find it in a while.

Here’s a nice little discussion on different sort methods people came up with, and the best of one of all as well:

http://groups.google.com/group/macromedia.flash.actionscript/
browse_frm/thread/831835576870f132?tvc=1&hl=en

Your example makes use of the custom sorting algorithm described in the article. In your case, you’re supplying the parameter as a function literal, which is perfectly fine. The function itself relies on two factors: the global random() function, which returns a pseudo-random integer between zero and one less than the number given, and the conditional operator.

random(2);
// returns either 0 or 1
random(3);
// returns 0, 1, or 2
// etc.

The ActionScript Language Reference recommends the Math.random() method over the random() function, which was deprecated in Flash 5. Math.random() is a bit different in that it accepts no parameters and returns a pseudo-random float greater than or equal to zero and less than one. You would need to use Math.round() in addition to Math.random() to achieve the same effect as random() alone.

Math.round(Math.random());

The conditional operator works like this …

(expression) ? result1 : result2

… in which an expression is evaluated as true or false. If true, the first result is returned; if false, the second is returned.

In your case, the expression is random(2), which I’ll update to the newer version …

(Math.round(Math.random())) ? 1: -1;

Remember, the number 1 represents true and 0 represents false, so that provides what the conditional operator needs. If the expression evaluates to true, the number 1 will be returned, which means element A will be positioned ahead of element B. If the expression evaluates to false, the number -1 will be returned, which means the opposite.

So rather than an expression like a > b, which is entirely predictable (element A is either greather than element B or it isn’t), you’re providing a random algorithm, which effectively “shuffles” your array.