Reading the clarified question in random negative toggle function reminded me of an question that's been bothering me for a while. Say I have an array with N elements, which I want to randomly set to either 0 or 1 but have a total of M (<=N). I know I can loop M times finding a random 0-element to switch to a 1 element (or if M > N/2, initializing all to 1 and setting N-M elements to 0), but is there a way to do it sequentially and yet insure a random distribution?

If I just loop through, giving each element a chance to be set of (how many ones left to assign) over (how many elements are left), it seems to me that that will distort the distribution toward the end.

Update: Many thanks to all who replied. What I was looking for was a random distribution, not an even distribution, and with a total of M, not an total averaging M, determined sequentially. Abigail-II's answer fits. Using the List::Util::shuffle to prepare a sequence and pulling elements off of it as I go through the real data also would fit the bill.

In reply to random elements with fixed totals by ysth

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