MATLAB Programming Fundamentals - MathWorks

Types of Functions

In this section...

“Local and Nested Functions in a File” on page 20-20

“Private Functions in a Subfolder” on page 20-21

“Anonymous Functions Without a File” on page 20-21

Local and Nested Functions in a File

Program files can contain multiple functions. Local and nested functions are useful for

dividing programs into smaller tasks, making it easier to read and maintain your code.

Local functions are subroutines that are available within the same file. Local functions are

the most common way to break up programmatic tasks. In a function file, which contains

only function definitions, local functions can appear in the file in any order after the main

function in the file. In a script file, which contains commands and function definitions,

local function must be at the end of the file. (Functions in scripts are supported in R2016b

or later.)

For example, create a function file named myfunction.m that contains a main function,

myfunction, and two local functions, squareMe and doubleMe:

function b = myfunction(a)

b = squareMe(a)+doubleMe(a);

end

function y = squareMe(x)

y = x.^2;

end

function y = doubleMe(x)

y = x.*2;

end

You can call the main function from the command line or another program file, although

the local functions are only available to myfunction:

myfunction(pi)

ans =

16.1528

20 Function Basics