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Random Function
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Argument
limit Optional; a positive integer expression representing the
upper limit of a range for random values
Returns
Real If no argument is passed, a real number in the range
0 <= returnvalue < 1
Word If a limit is passed, a whole number in the range
0 <= returnvalue < limit
Description
The Random function is a pseudorandom-number generator. Each call
to Random returns one number. If no argument is passed, Random
returns a real number greater than or equal to 0 but less than
1. If a limit argument is passed, Random returns a word
containing an integer greater than or equal to 0 but less than
the limit. If a limit of 1 is passed, Random returns 0.
Random takes a starting value from RandSeed, defined in the System
unit, and produces a sequence of numbers. Each call to Random
returns one number and sets RandSeed to a new value. If RandSeed is
not initialized to some value before the first call to Random,
Random generates a predictable sequence based on RandSeed's initial
value of 0.
Initialize RandSeed to an unpredictable value by a call to the
Randomize procedure or to a specified value by an assignment to
RandSeed. Random always generates the same number sequence when a
given starting value is in RandSeed. To reproduce a known random
series previously generated by Random, set RandSeed to the known
starting value.