Question

I am not sure if any language(preferably C# .NET) supports non-uniform random number generator. Is there any? I was wondering what could be the best design approach to implement our own non-uniform random number generator?

Thanks.

Answer 1

I was able to created semi non uniform distribution using uniform distribution for my requirements. Basically I generate the required M numbers from 1 to N range and then again just generate (N-M) numbers and throw them away. Like this way when I generate next set of numbers, I get almost equal probability for all numbers between 1 to N. It worked for me!

Example code in C#:

        int low=1, high=50;
        Random random = new Random();
        int total = 50;
        ArrayList set_nos = new ArrayList();

        while (--total > 0)
        {
            int set = 6;
            int loop = 0;
            while (--set > 0)
            {
                int temp = random.Next(low, high);
                loop++;
                if (set_nos.Contains(temp))
                    continue;

                set_nos.Add(temp);
            }

            for (int unused = 1; unused < high-loop; unused++)
                random.Next(low, high);

            //Use set_nos for your purpose!

        }