Texas Instruments TI-NSPIRE Software Manual page 47

Here are some examples:
Variable name
Myvar
My var
a
Log
Log1
3rdTotal
Preventing name conflicts
A TI-Nspire™ shared variable can have the same name as a table cell or
column letter. To help you prevent name conflicts in your table formulas,
Lists & Spreadsheet provides syntax rules.
• To refer to a variable whose name could conflict with the name of a
cell (such as A1), precede the variable name with an apostrophe
('A1).
• To refer to a table column (such as A) without conflicting with a
single-letter variable name A, follow the column letter with a pair of
brackets (A[]).
Use this
syntax: To refer to:
myvar The shared variable
myvar.
A1 The table cell at
column A, row 1.
The shared variable A1. The apostrophe makes this a
'A1
The shared variable A.
A
A[] Column A of the
current table.
Working with Documents
Valid?
Yes
No. Contains a space.
Yes
No. Name is preassigned to the
Yes
No. Starts with a digit.
Remarks
No special syntax is needed,
because this name does not conflict
with a cell or column reference.
This syntax always refers to table
cell A1—never to variable A1.
reference to variable A1—never to
table cell A1.
This syntax never refers to column
A.
Brackets make this a reference to
column A—never to variable A.
function.
log( )
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