Sharp MZ-700 Owner's Manual page 26

2.2.3 Arrays
Arrays can be thought of as shelves within the computer's memory which contain rows of boxes, each
of which represents a variable. The boxes on these shelves are arranged in an orderly sequence, and are
identified by means of numbers; these numbers are referred to as subscripts, because they are subscripted
to the name which identifies the entire group of boxes.
Such shelves of boxes are set up simply by executing an instruction which declares that they exist;
this is referred to as making an array declaration. The array declaration specifies the number of boxes
which are to be included in each set of shelves (i.e., the size of the shelves) and the manner in which
they are to be arranged.
The boxes in each unit of shelves may be arranged in sequences which have any number of dimensions.
Thus, a one-dimensional array can be thought of as a single shelf which holds, one row of boxes; a two-
dimensional array can be thought of as a stack of shelves, each of which holds one row of boxes; and
so forth. These boxes, or variables, are referred to as the array's elements.
The number of subscripts used to identify each of the array elements of a corresponds to the number
of dimensions in that array. For example, each of the elements in a one-dimensional array is identified by
a single subscript which indicates the box's position in the row; each of the elements in a two dimensional
array is identified by two subscripts, one which identifies the box's row, and one which indicates the box's
position within that row; and so forth. The numbers which are used as the subscripts start with zero, and
have a maximum value which is determined by the size of each of the array's dimensions (i.e., the number
of boxes in each row, etc.).
The maximum size of an array is limited by the amount of free space which is available in the com-
puter's memory (i.e., by the size of the program, the number of items of data which are to be stored
in the array, and so forth). The syntax of BASIC places no restrictions on the number of dimensions
which can be used for any array, but in practice the number of dimensions is limited by the amount of
free memory space which is available for storage of array variables.
An array must be declared before values can be stored in any of its elements.
~~GAC2~
·--·--
GA(IO~
A (100)
The variables making
up an array are referred
to as its elements.
A (3, 3, 3)
A one-dimensional array
consisting of 101 elements.
A (10, 10)
A two-dimensional array
consisting of 11 x 11 elements.
A three-dimensional array
consisting of 4 x 4 x 4 elements.
24------------------------------------------------------------------------