Variables store numbers, strings, file descriptors, or select lists and can change dynamically throughout the execution of the program.

Values can be assigned with an assignment statement. Assignment statements assign the value of an expression to a variable. Variables can be:

  • Simple variables
  • Array elements
  • Dynamic array elements
  • Substrings

For example var=x+2 assigns the value of the expression x+2 to the variable var.

A program variable is similar to a mathematical variable found in formulas.

A numeric string, when used in an arithmetical expression, is converted to a numeric expression, and a numeric expression is converted to a string expression when used with a string operator.

A variable name identifies the variable. Variable names consist of an alphabetical character that can be followed by additional letters, numerals, periods, dollar signs, and the underscore character. The length of a variable name can be from 1 to 48 characters. Up to 214,748,363 variables can be defined.