HP Prime Graphing Calculator - Manual (Page 214)

210 Spreadsheet
relevant cell. For example, wherever it is placed g5(1):=6543
enters 6543 in cell g5. Any previous content in g5 is replaced.
Similarly, B3(5):=2 forces the contents of B3 to be displayed in
medium font size.
Spreadsheet functions
As well as the functions on the Math, CAS and Catlg menus,
you can use special spreadsheet functions. These can be found
on the App menu, one of the Toolbox menus. Press
D , tap
and select Spreadsheet. The functions are described
on “Spreadsheet app functions” on page 349.
Remember to precede a function by an equals sign (
S. )
if you want the result to automatically update as the values it is
dependent on change. Without an equals sign you will be
entering just the current value.