SIMSCRIPT II.5 Programming Language

⎧
⎪
ELEMENTS
X(1)
X(2)
BASE POINTER ⎪ X(3)
X(*) ⎨ X(4)
⎪
⎪
⎪
⎪
⎪
⎩
X(5)
X(6)
X(7)
X(8)
X(9)
X(10)
Figure 6-1. One-dimensional Array X with Its Base Pointer
A three-dimensional array is structured similarly. The base pointer points to an array of row pointers,
each of which points to an array of column pointers, each of which, in turn, points to an array
of element variables. A three-dimensional array X, which has been allocated storage by the statement:
reserve X(*,*,*) as 5 by 3 by 2
is stored as shown in figure 6-3. Every element reference with at least one asterisk in its subscript
list is a pointer. Every fully subscripted element reference, that is, with no asterisk occupying any
subscript position, is a reference to a single element variable. In internally evaluating an element
reference, pointers are cascaded from one dimension to another, using subscripts from left to right.
⎧
⎨
⎩
ELEMENTS
X(1,1)
X(1,2)
X(1,3)
⎧
X(2,1)
ROW POINTERS ⎨ X(2,2)
⎧ X(1,*) ⎩ X(2,3)
BASE POINTER ⎪ X(2,*)
X(*,*) ⎨ X(3,*) ⎧ X(3,1)
⎪ X(4,*) ⎨ X(3,2)
⎩ X(5,*) ⎩ X(3,3)
⎧
⎨
⎩
X(4,1)
X(4,2)
X(4,3)
⎧
⎨
⎩
Figure 6-2. Base Pointers in a Two-Dimensional Array
X(5,1)
X(5,2)
X(5,3)
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