SIMSCRIPT II.5 Programming Language

Advanced Topics
Attributes:
HIGH
LOW
. .
. .
. .
word N
HIGH and LOW are synonyms. Both are pointers to the same attribute array. This is an array because
the background dimensionality is set to 1.
(4) Declaration:
normally mode is integer, dimension is 1
the system has a ( HIGH(1/4), LOW(2/2) )
Attributes:
HIGH word 1 unused LOW
word 2
. .
. .
. .
word N
The elements of the attribute arrays are packed in the same locations as of a shared data array. The
second quarter of each data word is unused.
Intrapacking is used to compress array storage of subscripted system attributes and attributes of permanent
entities. The intrapacking notation (*/2) specifies that two distinct element values are to
be packed in each storage location. That is, the array in which the elements are stored is compressed.
For example, the declarations:
normally dimension is 1
the system has a LIST(*/2)
and the statement reserve LIST(*) as 10 specifies and allocates storage to LIST as shown in
figure 6-11.
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