Apple Numbers '08 - Manual (Page 213)

Chapter 12 Dictionary of Functions 213
Notes
Not all numbers in a character are associated with a printable character.
You can use the Character Palette, which you can enable in International preferences,
to view entire sets of characters and their codes.
You can use the CODE function to find the numeric code for a specific character.
CHOOSE
The CHOOSE function uses a specified index value to retrieve a value from a set of
values.
CHOOSE(index, value, [value, . . .])
 index: A numeric expression.
 value: One or more values, which can be text, a numeric expression, or a cell
reference.
CLEAN
The CLEAN function removes most common nonprinting characters (Unicode character
codes 0–31) from text. This can be helpful if text you paste from another application
contains unwanted question marks, spaces, boxes, or other unexpected characters.
CLEAN(text)
 text: The text from which you want to remove nonprinting characters.
Notes
There are some less common nonprinting characters that are not removed by CLEAN
(character codes 127, 129, 141, 143, 144, and 157). To remove these, you can use the
SUBSTITUTE function to replace them with a code in the range 0–31 before you use the
CLEAN function.
You can use the TRIM function to remove extra spaces in text.
Examples
CHAR(98.6) returns "b", which is represented by the code 98.
CODE("b") returns 98.
Examples
If cells A1:A7 contain Monday, Tuesday, Wednesday, Thursday, Friday, Saturday, Sunday:
CHOOSE(4, A1, A2, A3, A4, A5, A6, A7) returns Thursday.
CHOOSE(3,"1st","second",7,"last") returns 7, the third value in the list.