VARIABLES Your computer uses three types of variables in BASIC. These are: normal numeric, integer numeric, and string (alphanumeric) variables. NUMERIC VARIABLES Normal numeric variables, also called floating point variables, can have any value from ^ -38 to ^ +38, with up to nine digits of accuracy. When a number becomes larger than nine digits can show, as in 10 ^ -10 or 10 ^ +10, your computer displays it in scientific notation form, with the number normalized to 1 digit and eight decimal places, followed by the letter E and the power of ten by which the number is multiplied. For example, the number 12345678901 is displayed as 1.23456789E+10. INTEGER VARIABLES Integer variables can be used when the number is from +32767 to -32768, and with no fractional portion. An integer variable is a number like 5, 10, or -100. Integers take up less space than floating point variables when used in an array. STRING VARIABLES String variables are those used for character data, which may contain numbers, letters, and any other character that your computer can make. An example of a string variable is "COMMODORE 16". VARIABLE NAMES Variable names may consist of a single letter, a letter followed by a number, or two letters. Variable names may be longer than 2 characters, but only the first two are significant. An integer variable is specified by using the percent (%) sign after the variable name. String variables have the dollar sign ($) after their names. Examples: Numeric Variable Names: A, A5, BZ Integer Variable Names: A%, A5%, BZ% String Variable Names : A$, A5$,BZ$ ARRAYS Arrays are lists of variables with the same name, using an extra number (or numbers) to specify an element of the array. Arrays are defined using the DIM statement, and may be floating point, integer, or string variables arrays. The array variable name is followed by a set of parentheses ( ) enclosing the number of the variable in the list. Examples: A(7), BZ%(11), A$(87) Arrays may have more than one dimension. A two dimensional array may be viewed as having rows and columns, with the first number identifying the column and the second number in the parentheses identifying the row (as if specifying a certain grid on a map). Examples: A(7,2), BZ%(2,3,4), A$(3,2) RESERVED VARIABLE NAMES There are seven variable names which are reserved for use by the computer, and may not be used for another purpose. These are the variables: DS DS$ EL ER ST TI TI$