Creating Custom Functions
E. Joseph Billo · 2001
Chapter 13 provided an introduction to Sub procedures and Function procedures. By now it should be clear that a Sub procedure (a command macro) is a computer program that the user can “run”; it can perform actions such as formatting, opening or closing documents, etc. A Function procedure (a user-defined function) is a computer program that calculates a value and returns it to the cell in which it is typed. A Function procedure cannot change the worksheet environment (e.g., it can't make a cell Bold). This chapter provides some examples of more advanced custom functions.