Step-by-Step Guide to Call a Function in MATLAB from Another File

MATLAB is a powerful programming language used for technical computation and visualization tasks. It can be used to design, analyze and present various types of data. One useful feature that is available in MATLAB is the ability to call a function from another file. That way, the same code can be reused within multiple scripts. This guide will explain how to do that in MATLAB.

Requirements

In order to call a function in MATLAB from another file, the following requirements must be met:

  • MATLAB must be installed on your machine.
  • The function must be saved in a .m file.
  • The PATH environment variable must include the folder containing the function.
  • The file containing the function that is being called must be on the MATLAB path.

Steps

Make sure the folder containing the MATLAB function(s) is included in the MATLAB path. To do this:

  • Open MATLAB and go to File > Set Path.
  • Select the folder you wish to add and click Add with Subfolders.
  • Click Save and then Close.

Create a script to be run, let’s call it run.m.

In the run.m file, write the code for the function you want to call from another file.

Make sure to include the function’s name, arguments and the keyword end:

function [output] = run(arg1, arg2) 
    [output] = myFunction(arg1, arg2); 
end

Inside the run.m file, call the function using feval. The structure should be:

[output] = feval('myFunction', arg1, arg2); 

Replace myFunction with the name of your function and arg1 and arg2 with the names of the variables you defined in step 3.

Save and run the script.

The output of the script should now be the output of the function you defined in another file.

FAQ

How can I tell if the function was successfully called in MATLAB?

You can check the Command Window to see if the script ran. The output should be the output of the function you wanted to call.

What is the difference between using feval and writing the code directly?

Using feval to call the function allows you to use the same code in multiple scripts without having to rewrite it. This can save a lot of time and makes it easier to keep track of code.

Can I call a function from another file even if the file is not on the MATLAB path?

No, the file containing the function must be included in the MATLAB path in order for the function to be called.

Does MATLAB support functions with multiple arguments?

Yes, MATLAB supports functions with up to 12 arguments.

How can I add more than one folder to the MATLAB path?

You can add multiple folders to the MATLAB path by repeating the steps outlined in the Requirements section.

Great! You’ve successfully signed up.

Welcome back! You've successfully signed in.

You've successfully subscribed to Lxadm.com.

Success! Check your email for magic link to sign-in.

Success! Your billing info has been updated.

Your billing was not updated.