## ISALPHA Test for Alpha Characters in a String

Section: String Functions

### Usage

The `isalpha` functions returns a logical array that is 1 for characters in the argument string that are letters, and is a logical 0 for characters in the argument that are not letters. The syntax for its use is

       x = isalpha(s)

where `s` is a `string`. Note that this function is not locale sensitive, and returns a logical 1 for letters in the classic ASCII sense (a through z, and A through Z).

### Example

A simple example of `isalpha`:

    --> isalpha('numb3r5')

    ans =

     1 1 1 1 0 1 0