HP Prime Graphing Calculator - Manual (Page 113)

An introduction to HP apps 109
Sequence app—see chapter 17, “Sequence app”, beginning on
page 279.
As well as cloning a built-in app—as described above—you can
modify the internal workings of a customized app using the HP
Prime programming language. See “Customizing an app” on
page 521.
App functions and variables
Functions App functions are used in HP apps to perform common
calculations. For example, in the Function app, the Plot view Fcn
menu has a function called SLOPE that calculates the slope of a
given function at a given point. The SLOPE function can also be
used from the Home view or a program.
For example, suppose you want to find the derivative of x
2 – 5 at
x = 2. One way, using an app function, is as follows:
1. Press
D .
2. Tap and select Function > SLOPE.
SLOPE() appears on the entry line, ready for you to specify
the function and the x-value.
3. Enter the function:
Asjw 5
4. Enter the parameter
separator:
o
5. Enter the x-value and press
E .
The slope (that is the
derivative) at x = 2 is
calculated: 4.
All the app functions are described in “App menu”, beginning on
page 343.
Variables All apps have variables, that is, placeholders for various values
that are unique to a particular app. These include symbolic
expressions and equations, settings for the Plot and Numeric
views, and the results of some calculations such as roots and
intersections.