SIMSCRIPT II.5 Programming Language

SIMSCRIPT II.5 Programming Language
Table 5-9. Accumulate Computations
N.QUEUE
(1)
Time Value
Began
(2)
Time Value
Ended
(3)
Increment
(4)=(3)-(2)
Area
(5)=(1)*(4)
Sum
(5)
0 0 1.2 1.2 0 0
1 1.2 3.0 1.8 1.8 1.8
3 3.0 4.6 1.6 4.8 6.6
2 4.6 6.1 1.5 3.0 9.6
3 6.1 8.0 1.9 5.7 15.3
4 8.0 8.3 0.3 1.2 16.5
5 8.3 11.2 2.9 14.5 31.0
2 11.2 12.4 1.2 2.4 33.4
1 12.4 14.1 1.7 1.7 35.1
0 14.1 17.1 3.0 0 35.1
1 17.1 18.0 0.9 0.9 36.0
The sums in table 5-9 are maintained for the computation of AVG.QUEUE(1). If, at simulated time
11.2 (time.v=11.2), AVG.QUEUE(1) appears in a statement such as list AVG.QUEUE(1),
it is computed from table 5-9 data as 31.0/11.2=2.77. That is, the average number of jobs in
QUEUE(1) from time.v=0 to time.v=11.2 is 2.77. If at some time between changes in
N.QUEUE(1), say at time.v=0, a value for AVG.QUEUE(1) is requested, it is computed as
[16.5+5(10-8.3)]/10=2.5 by the function AVG.QUEUE.
More complete information on the values attained by tallied global variables, system attributes, and
attributes of permanent entities can be obtained by requesting a frequency count of the number of
times a variable takes on specified ranges of values. Statements of the form:
tally name1 (r1 to r2 by r3) as the histogram of name2
define an array name1 with (r2 - r1)/r3 + 1 elements, one for each element of name2, plus an additional
element for overflows. If name2 is the name of a permanent attribute, an array of histograms
will be defined. The interval between r2 and r1 is divided into classes r3 units wide. If a
sample falls between r1 and r1 + r3, the value of the element name1(1) is incremented by 1. If
it falls between r1 + r3 and r1 + 2r3, name1(2) is incremented, and so forth.
Thus, the average value of a variable, and the distribution of values it takes at different times, over
the duration of a simulation run, may be requested by preamble statements such as:
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