🚀 go-pugleaf

In article <1992Aug20.864.127@ALMAC>, keith.willis@almac.co.uk writes:
>        This is fine as a random bitstream, but for his application,
>        he needs a set of random _values_, in a defined range, with

You can convert from a random bitstream to a stream of random discrete
values (let's say, integers from 0..R) by the following algorithm.

    Determine N, the number of bits you need (lowest N such that 2**N > R)

    while (more bits available)
        construct integer X out of next N bits (X = b(1)+2*b(2)+4*b(3)+...)
        if X <= R
            output X to stream
        else
            do nothing (discard bad X)
    endwhile

For ranges that are exactly a power of two, this algorithm works perfectly. 
For other ranges, it may discard (waste) almost half your bitstream.

>        the constraint that there must be at least one of each
>        possible value.  

At least one of each possible value?  That's a weird requirement.  Could you
just add a list of all possible values onto the end of the stream?

Keith Lewis             klewis@mitre.org          "Mr. Cheap"
I don't dance to music; music dances to me.  Email me for my PGP key.
The above may not (yet) represent the opinions of my employer.