isvarname

Determine if input is valid variable name

Syntax

tf = isvarname(s)

isvarname s

Description

tf = isvarname(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 not 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 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.

Examples

Determine Variable Name Validity

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

s = '8th_column';
isvarname(s)

ans = logical
   0

Change the input to a valid variable name.

s = 'column_8';
isvarname(s)

ans = logical
   1

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

isvarname column_8

ans = logical
   1

Input Arguments

s — Potential variable name

character vector | string

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

Example: 'myVar'

Example: "myVar2"

Extended Capabilities

Thread-Based Environment

Run code in the background using MATLAB® backgroundPool or accelerate code with Parallel Computing Toolbox™ ThreadPool.

This function fully supports thread-based environments. For more information, see Run MATLAB Functions in Thread-Based Environment.

Version History

Introduced before R2006a