Here - 1000 BiT

D^ INSTRUCTOR NOTES 30 ARRAYS AND THE DIM COMMAND^ This lesson introduces arrays. The DIM() statement is described. Up to 255 indices are^allowed.r*) Arrays with one index are described first. The array itself is compared to a family, andthe individual elements of the array to family members, with the index value being theO"first name" of the member.Two dimensional arrays can be compared to the numbers on a calendar month page or^ the rectangular array of cells on the TV screen.f*) Arrays themselves are not too difficult a concept. The trick is to see how they help inprogramming. There are a large variety of uses for arrays, and many do not seem to fall^ into recognizable catagories.One can use them to store lists of information. Connected lists also can occur. The^ telephone number program uses two linear arrays: one for names, the other for numbers.They are indexed the same, so a single index number can retrive both the name and ther*snumber which goes with it.^ Another general use of arrays is to store numbers which cannot neatly be obtained from^ an equation. An example would be the length in days of the 12 months.^ Games often use arrays to store information about the playing board.^If you forget to DIMension an array before use, the BASIC interpreter gives it a dimension of10. If you try to use an element larger than that assigned to the array, the^ ?BAD SUBSCRIPT ERROR IN XXr*) message is printed.QUESTIONS:^ 1. What does the DIM BD(6) statement do?r^ 2. Where do you put the DIM command in the program?(^ 3. What two kinds of array families are there?4. What is the "index" or "subscript" of an array?n169