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- DEFINITION MODULE Random;
- (*
- Random number generator.
- Uses the 'Minimal standard random number generator' described by
- Park & Miller, CACM 31,10,Oct 88 p1192. The code has been checked
- for the 10001st random as specified in Park & Miller p1195.
- This version returns a REAL randomly distributed in the closed range
- [0.0,1.0], and will be correct if the real mantissa is 46 bits
- or larger (including sign bit). The sequence is guaranteed to produce
- all values of the form n/m for n = 0 to m, where m is 2147483646
- (=2**31-2), before cycling.
- *)
- PROCEDURE InitRandom (seed : REAL);
- (* Initialise the random number generator with the given seed. *)
- (* The seed should be in the range [1.0,2147483646.0] - values outside *)
- (* this range are clamped to the extreme values. *)
- (* If InitRandom is not called, the system clock is used to initialise *)
- (* the sequence; thus InitRandom must be called to create a *)
- (* reproducible sequence. *)
- (* InitRandom may be called as often as needed. *)
- PROCEDURE Random() : REAL;
- (* Return the next pseudo-random number in the closed range [0.0,1.0] *)
- END Random.
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