SIMSCRIPT II.5 Programming Language

SIMSCRIPT II.5 Programming Language
5.4.1 Random Step Variables
If the sampling variable is defined by the statement:
the system has a SAMPLE random step variable
sampling is done as follows in the statement let X = SAMPLE:
1. A random number is drawn from random.f(1)
2. This random number is compared with successive cumulative probability values until a value
is found that equals or exceeds it
3. The column 2 value (table 5-6) associated with this cumulative probability value is returned
as the value of the sample. Examples are:
If the random number drawn is 0.20, SAMPLE = 2.5
If the random number drawn is 0.45, SAMPLE = 11.8
If the random number drawn is 0.65, SAMPLE = 30.0
If the random number drawn is 0.95, SAMPLE = 50.0
5.4.2 Random Linear Variables
Random variables defined as step can be either integer- or real-valued. If the sampling variable
is defined by the statement:
the system has a SAMPLE random linear variable
sampling is done as follows:
1. A random number is drawn from random.f(1)
2. This random number is compared with successive cumulative probability values until a value
is found that equals or exceeds it
3. Interpolation is done between the column 2 value (table 5-6) associated with the stopping
cumulative probability value and the column 2 value preceding it. If i represents the index
of the stopping probability, C(i) the probability, and V(i) the sample value, the interpolation
formula is:
SAMPLE = V(i-1) + random.f - C(i-1) [V(i) - v(i-1)]
C(i) - C(i-1)
Examples are:
If the random number drawn is 0.20, SAMPLE = 2.5
If the random number drawn is 0.45, SAMPLE = 11.8
If the random number drawn is 0.65, SAMPLE = 23.6
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