12 Chapter 1: Operating the TIN73
7301ENG.DOC CH1 Operating the TI-73, English Julie Hewlett Revised: 07/29/98 11:55 AM Printed: 05/19/99
8:58 AM Page 12 of 24
Functions and Instructions
A function returns a value. Generally, the first letter of each
function is lowercase on the TIN73. For example, pxl-Test( is a
function because it returns a value, 0 or 1.
An instruction initiates an action. Generally, the first letter of
each instruction name is uppercase. For example, Pxl-On( is an
instruction that draws a pixel on the graph screen.
Most functions and some instructions take at least one
argument. An open parenthesis (() at the end of the function or
instruction name prompts you to enter an argument. Complete
the function with an end parenthesis, E.
Note: Do not use the Text editor to enter names of functions
or instructions. For example, you cannot enter L, then O, then
G to calculate the log of a value. If you did this, the calculator
would interpret the entry as implied multiplication of the
variables L, O, and G.
When this guidebook describes the syntax of a function or
instruction, each argument is in italics. Optional arguments for
a function are signified by brackets [ ]. Do not enter the
brackets.

Accessing Functions and Instructions from MenusAccessing Functions and Instructions from Menus

You can find most functions and instructions on menus (in
other words, not directly from the keyboard).

Displaying a Menu

To display a menu, press the key associated with the menu. Up
to four separate menus are displayed from which you choose
the menu item you want.
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