HP 48gII hp 48gII_user's manual_English_E_HDPMSG48E67_V2.pdf - Page 159

Defining and using functions Users can define their own functions by using the DEF command available thought the keystroke sequence „à (associated with the 2 key). The function must be entered in the following format: Function_name(arguments) = expression_containing_arguments For example, we could define a simple functionH(x) = ln(x+1) + exp(-x). Suppose that you have a need to evaluate this function for a number of discrete values and, therefore, you want to be able to press a single button and get the result you want without having to type the expression in the righthand side for each separate value. In the following example, we assume you have set your calculator to ALG mode. Enter the following sequence of keystrokes: „à³~h„Ü~„x x+1 x` The screen will look like this: Press the J key, and you will notice that there is a new variable in your soft menu key (@@@H@@). To see the contents of this variable press ,@@@H@@. The screen will show now: Thus, the variable H contains a program defined by: > This is a simple program in the default programming language of the HP 48 G series, and also incorporated in the HP 49 G series. This programming language is called UserRPL. The program shown above is relatively simple and consists of two parts, contained between the program containers >: Page 3-34