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Lehmer's Method for shuffling is the simplest, and is completely analysable.
- 1.
- Multiply the current value, xj, by magic1, a constant.
- 2.
- Reduce the result modulo magic2, another constant,
and post in xj+1.
In FORTRAN this might look like:
x(j) = MOD(x(j - 1)*magic1,magic2)
This scheme leads to a complete, shuffled set of the integers from 1
through (magic2-1) if certain constraints on magic1 and
magic2 are met.
Next: A simple shuffle
Up: GENERATING RANDOM SEQUENCES
Previous: GENERATING RANDOM SEQUENCES
Stanford Exploration Project
11/18/1997