In the PROMOTIC system it is better to use the Pm.Random method.
n = Rnd[(number)]
|number||(Integer) Any valid numeric expression. The value of parameter specifies determines how it generates a random number.|
less than 0 - The same number every time, using number as the seed.
greater than 0 - The next random number in the sequence.
equal to 0 - The most recently generated number.
if not supplied - the next random number in the sequence.
For any given initial seed, the same number sequence is generated because each successive call to the Rnd function uses the previous number as a seed for the next number in the sequence.
Before calling Rnd, use the Randomize statement without an argument to initialize the random-number generator with a seed based on the system timer.
To produce random integers in a given range, use this formula:
Int((upperbound - lowerbound + 1) * Rnd + lowerbound)
where upperbound is the highest number in the range, and lowerbound is the lowest number in the range.
If it is necessary to repeat sequences of random numbers, then call Rnd with a negative argument immediately before using Randomize with a numeric argument. The usage of Randomize with the same value for number does not repeat the previous sequence.