SIMSCRIPT II.5 Programming Language

SIMSCRIPT II.5 Programming Language
2. The first of each pair is assumed to be a probability. The second is assumed to be a sample
value.
3. A system-defined, three-attribute entity, random.e, is created for each pair. The probability
value is assigned to its first attribute, prob.a. The sample value is assigned to its second
attribute, referred to as ivalue.a if the variable is integer, or rvalue.a if the
variable is real.
4. The entities are filed in a set having the same name as the random variable. The third attribute
in each random.e record is a pointer named s.variable.
5. Occupies the space declared for the random variable or attribute.
Input probabilities can be cumulative or individual. If cumulative, the last probability must be 1.0.
If individual, they must sum to 1.0. All random variables have their probabilities stored cumulatively.
If any probability appears as less than 0 or greater than 1, the program terminates with an
error message.
The following examples illustrate how random variables are defined and used.
Definition:
the system has a RANDVAR random step variable
define RANDVAR as an integer variable
Input statement:
Input data:
read RANDVAR
0.1 10 0.2 25 0.35 40 0.55 100 0.8 150 1.0 200 *
The sampling probabilities are expressed cumulatively in six pairs of sampling values. These pairs
are stored in six entities in a set named RANDVAR.
Storage of RANDVAR sample values is shown in figure 5-8.
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