Create Live Functions

Live functions are program files that contain code and formatted text together in a single interactive environment called the Live Editor. Similar to live scripts, live functions allow you to reuse sequences of commands by storing them in program files. Live functions provide more flexibility, though, primarily because you can pass them input values and receive output values.

Create Live Function

To create a live function, go to the Home tab and select New > Live Function.

Open Existing Function as Live Function

If you have an existing function, you can open it as a live function in the Live Editor. Opening a function as a live function creates a copy of the file and leaves the original file untouched. MATLAB^® converts publishing markup from the original script to formatted content in the new live function.

To open an existing function (.m) as a live function (.mlx) from the Editor, right-click the document tab and select Open functionName as Live Function from the context menu.

Alternatively, go to the Editor tab, click Save, and select Save As. Then, set the Save as type: to MATLAB Live Code Files (*.mlx) and click Save.

Note

You must use one of the described conversion methods to convert your function to a live function. Simply renaming the function with a .mlx extension does not work and can corrupt the file.

Create Live Function from Selected Code

If you have an existing large live script or function, you can break it into smaller pieces by automatically converting selected areas of code into functions or local functions. This is called code refactoring.

To refactor a selected area of code, select one or more lines of code and on the Live Editor tab, in the Code section, click Refactor. Then, select from the available options. MATLAB creates a function with the selected code and replaces the original code with a call to the newly created function.

Add Code

After you create the live function, add code to the function and save it. For example, add this code and save it as a function called mymean.mlx. The mymean function calculates the average of the input list and returns the results.

function a = mymean(v,n)    
    a = sum(v)/n;
end

Add Help

To document the function, add formatted help text above the function definition. For example, add a title and some text to describe the functionality. For more information about adding help text to functions, see Add Help for Live Functions.

mymean live function with a title, descriptive text, and code

Run Live Function

You can run live functions using several methods, including calling them from the Command Window or calling them from a live script. In MATLAB Online™, you also can use the Run button.

To run a live function from the Command Window, enter the name of the function in the Command Window. For example, use mymean.mlx to calculate the mean of 10 sequential numbers from 1 to 10.

mymean(1:10, 10)

ans =
    5.5000

You also can call the live function from a live script. For example, create a live script called mystats.mlx. Add this code that declares an array, determines the length of the array, and passes both values to the function mymean.

x = 1:10;
n = length(x);
avg = mymean(x,n);
disp(['Average = ', num2str(avg)])

Run the live script. The Live Editor displays the output.

Live script with the output of mymean to the right of the disp statement used to display it

If a live function displays text or returns values, the Live Editor displays the output in the calling live script, in line with the call to the live function. For example, add a line to mymean that displays the calculated mean before returning the value:

function a = mymean(v,n)
    a = sum(v)/n;
    disp(['a = ', num2str(a)])
end

When you run mystats, the Live Editor displays the output for mymean with the output from mystats.

Live script with the output from mymean displayed to the right of the call to mymean, and again to the right of the disp statement used to display it

In MATLAB Online, you can use the Run button to run live functions interactively. When you run a live function using the Run button, the output displays in the Command Window. To run live functions that require input argument values or any other additional setup, configure the Run button by clicking Run and adding one or more commands. For more information about configuring the Run button, see Configure the Run Button for Functions.

Save Live Functions as Plain Code

To save a live function as a plain code file (.m):

On the Live Editor tab, in the File section, select Save > Save As....
In the dialog box that appears, select MATLAB Code files (UTF-8) (*.m) as the Save as type.
Click Save.

When saving, MATLAB converts all formatted content to publish markup.