isvarname - Determine if input is valid variable name - MATLAB (original) (raw)

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Determine if input is valid variable name

Syntax

Description

tf = isvarname([s](#f72-1047442-s)) determines if input s is a valid variable name. If s is a valid MATLAB® variable name the isvarname function returns logical 1 (true). Otherwise it returns logical 0 (false).

A valid variable name begins with a letter and contains no more than namelengthmax characters. Valid variable names can include letters, digits, and underscores. MATLAB keywords are not valid variable names. To determine if the input is a MATLAB keyword, use the iskeyword function.

isvarname [s](#f72-1047442-s) is the command form of the syntax. The command form requires fewer special characters. You do not need parentheses or single quotes around the input.

example

Examples

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Show that input that starts with a number is not a valid variable name.

s = '8th_column'; isvarname(s)

Change the input to a valid variable name.

s = 'column_8'; isvarname(s)

Use the command form to determine if the input is a valid variable name.

Input Arguments

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Potential variable name, specified as a character vector, or string.

Example: 'myVar'

Example: "myVar2"

Extended Capabilities

Version History

Introduced before R2006a

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The maximum allowed identifier length is increased to 2048. This change allows variables, functions, classes, and many other entities to have names of up to 2048 characters. Longer identifiers negatively impact performance and memory.