SIMSCRIPT II.5 Programming Language

Modelling Concepts
4.14.3 An Analysis of Prime Numbers
Program 4-3.
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preamble
normally mode is integer
the system owns the PRIMESET
temporary entities
every PRIME has a VALUE and belongs to the PRIMESET
end
main
read N
for I = 2 to N,
do
''CREATE PRIME NUMBERS
for each PRIME in PRIMESET
with MOD.F(I, VALUE) eq 0
find the first case
if none
create a PRIME
let VALUE.. = I
file PRIME in PRIMESET
always
loop
for each I of PRIMESET
with S.PRIMESET(I) ne 0
compute MAX = the max(I) of VALUE(S.PRIMESET(I)) - VALUE(I)
print 2 lines with N.PRIMES, VALUE(MAX),
VALUE(S.PRIMESET(MAX)) thus
MAXIMUM GAP AMONG THE FIRST **** PRIMES
OCCURS BETWEEN **** AND ****
stop
end
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4.14.4 Dynamic Definition and Use of Attributes
Because the notation for subscripting array elements is the same as that used for entity attributes,
there are obvious difficulties in attempting to directly reference elements of an array that is an attribute
of a temporary entity. In fact, this cannot be done. It is possible, however, to associate array
attributes with entities, through some explicit programming. The following statements illustrate
how to create, use, and destroy array attributes.
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