A Conceptual View of Arrays

One-Dimensional Array

The following figure is a conceptual representation of two one-dimensional arrays, MISC and MDAY.

Figure 25.1: One-Dimensional Array

MISC contains eight elements, the variables MISC1 through MISC8. To reference the data in these variables , use the form MISC{ n }, where n is the element number in the array. For example, MISC{6} is the sixth element in the array.

MDAY contains seven elements, the variables MDAY1 through MDAY7. MDAY{3} is the third element in the array.

Two-Dimensional Array

The following figure is a conceptual representation of the two-dimensional array EXPENSES.

First Dimension		Second Dimension
Expense Categories				Days of the Week			Total
		1	2	3	4	5	6	7	8
Hotel	1	hotel1	hotel2	hotel3	hotel4	hotel5	hotel6	hotel7	hotel8
Phone	2	phone1	phone2	phone3	phone4	phone5	phone6	phone7	phone8
Pers. Auto	3	peraut1	peraut2	peraut3	peraut4	peraut5	peraut6	peraut7	peraut8
Rental Car	4	carrnt1	carrnt2	carrnt3	carrnt4	carrnt5	carrnt6	carrnt7	carrnt8
Airfare	5	airlin1	airlin2	airlin3	airlin4	airlin5	airlin6	airlin7	airlin8
Dues	6	dues1	dues2	dues3	dues4	dues5	dues6	dues7	dues8
Registration Fees	7	regfee1	regfee2	regfee3	regfee4	regfee5	regfee6	regfee7	regfee8
Other	8	other1	other2	other3	other4	other5	other6	other7	other8
Tips (non-meal)	9	tips1	tips2	tips3	tips4	tips5	tips6	tips7	tips8
Meals	10	meals1	meals2	meals3	meals4	meals5	meals6	meals7	meals8

Figure 25.2: Example of a Two-Dimensional Array

The EXPENSES array contains ten groups of eight variables each. The ten groups (expense categories) comprise the first dimension of the array, and the eight variables (days of the week) comprise the second dimension. To reference the data in the array variables, use the form EXPENSES{ m,n }, where m is the element number in the first dimension of the array, and n is the element number in the second dimension of the array. EXPENSES{6,4} references the value of dues for the fourth day (the variable is DUES4).