SIMSCRIPT II.5 Programming Language

SIMSCRIPT II.5 Programming Language
define statements, depending on whether it is to apply as a background condition or to specifically
named arrays. The phrase is written somewhat differently in each case.
An n-dimensional array background condition may be declared with a normally statement using
the phrase:
dimension is n
as in the statements:
normally dimension is 1
normally, mode is integer, dimension is 2
In a define statement, a dimensionality specification can be made for a list of subscripted variables
with the dimensionality phrase n-dimensional as in the statements:
define LIST as an integer, 1-dimensional array
define LIST and VECTOR as real, 1-dimensional arrays
define CUBE as a 3-dimensional, integer array
In general, if a majority of program variables share some definable property, this may be declared
as a background condition, using a normally statement. Define statements may then be used to
override this specification for specific variables, as in the example:
preamble
normally, mode is integer, dimension is 2
define X, Y, Z and Q as real variables
define VECTOR as a 1-dimensional array
end
A variable must not, however, be used in more than one define statement. It is permissible to
write:
normally, mode is real, dimension is 1
define X as an integer, 0-dimensional variable
It is not permissible to write:
normally, mode is real, dimension is 1
define X as an integer variable
.
.
define X as a 0-dimensional variable
Each unsubscripted (zero-dimensional) variable requires a location in computer memory in which
to record its current value at any time. Similarly, each element of each array requires a distinct
memory location where its value can be stored. A one-dimensional array with 10 elements uses 10
such memory locations, a two-dimensional array with 3 rows and 5 columns uses (3*5) = 15 memory
locations, and so forth.
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