Re: Need help to custom the rand function ,

Fred wrote:
Hi guys,

I was wondering how could i get a random number exemple between 1 and
100 but with n% of getting some value over a number x.

Thanks a lot in advance.

Fred

Never mind Jerry, No one else does.


So you want a random number from a weighted distribution?


Your spec doesn't contain quite enough data to formulate the formula, since there are an infinite number of distributions that have N% over value X..

One example, is that you first of all get a random number between 0 and 100: If this is greater than N, then select a random number greater than X, else select one less than X.

So in pseudo code where RAND(X) returns a number between 0 and X-1...


if ((RAND(100))<N) THEN RETURN RAND(X) ELSE RETURN(X+RAND(100-X));



.

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