Functions and Subroutines

A function is an operation which produces a single result on some data and can be used as part of an expression. BASIC provides  a large number of utility functions which are part of BASIC language and are known as Built-in function (or Library functions). The data upon which the function acts to produce the desired result is known as argument of the function. The argument can be a variable, a constant or an expression. The argument is to be enclosed in a pair of brackets.

Example :

1. 10 PRINT ABS (X) 

2. 10 PRINT LEN ("COMPUTER")

The functions in BASIC can be divided into the following categories :

1. String function

2. Arithmetic function

3. Trigonometric function