Re: random numbers in fortran

Mark Morss wrote:

How, for example, would one set "cycle length" to be sure that each one
of 52! combinations had the same chance of coming up? My Fortran
reference is Chapman's _Fortran 90/95 for Scientists and Engineers_,
and in its brief discussion of the RANDOM_SEED and RANDOM_NUMBER
intrinsics, it makes no mention of "cycle length."

The cycle length is a property of the generator, so it's natural that it would not be mentioned in a pure discussion of the language -- the actual generator used by a particular compiler is a QofI issue.

As far as I know, most generators do have a reported cycle length. Ideally, the cycle length from RANDOM_NUMBER is included with the documentation of your favorite compiler.
.

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