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Add Help for Live Functions

You can provide help for the live functions you write. Help text appears in the Command Window when you use the help command. You also can use the doc command to display the help text in a separate browser.

Create help text by inserting text at the beginning of the file, immediately before the function definition line (the line with the function keyword).

For example, create a live function called addme.mlx with this code:

function c = addme(a,b)

switch nargin
    case 2
        c = a + b;
    case 1
        c = a + a;
        c = 0;
Add help text to describe the function.

addme live function with help text above the code, including the function's purpose, supported syntaxes, and related functions

When you type help addme in the Command Window, the help text displays.

Command Window with the help text for the addme live function displayed

The first line of help text, often called the H1 line, typically contains a brief description of the function. When displaying help for a function, MATLAB® first displays the name of the function followed by the H1 line. Then, MATLAB displays the syntax of the function. Finally, MATLAB displays any remaining help text.

To add "See also" links, add a text line at the end of the help text that begins with the words See also followed by a list of function names. If the functions exist on the search path or in the current folder, the help command displays each of these function names as a hyperlink to its help. Otherwise, help prints the function names as they appear in the help text.


When multiple programs have the same name, the help command determines which help text to display by applying the rules described in Function Precedence Order. However, if a program has the same name as a built-in function, the Help on Selection option in context menus always displays documentation for the built-in function.

To enhance the documentation displayed in the Help browser further, you can format the text and add hyperlinks, images, equations, and example code. For example, in the addme function, select the H1 line and in the Live Editor tab, change the Normal text style to Title. Then, position your cursor at the end of the second syntax description, go to the Insert tab, and select Equation. Enter the equation c = a + b and press Esc. Finally, in the Insert tab, select Code Example > MATLAB and add two examples. For more information about formatting files in the Live Editor, see Format Text in the Live Editor.

addme live function with formatted help text above the code, including a title, a formatted equation, and code examples

Use the doc command to display the help text in a separate browser.

Separate browser showing the formatted help text for the addme live function

You also can add help to live functions by inserting comments at the beginning of the file. Comments at the beginning of the file display as help text when you use the help and doc commands, similar to how text at the beginning of the file displays. For more information about adding help using comments, see Add Help for Your Program.

See Also

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