MATLAB Programming

Private Functions
Private Functions
Private functions are functions that reside in subdirectories with the special
name private. These functions are called private because they are visible
only to M-file functions and M-file scripts that meet these conditions:
• A function that calls a private function must be defined in an M-file that
resides in the directory immediately above that private subdirectory.
• A script that calls a private function must itself be called from an M-file
function that has access to the private function according to the above rule.
For example, assume the directory newmath is on the MATLAB search path. A
subdirectory of newmath called private can contain functions that only the
functions in newmath can call.
Because private functions are invisible outside the parent directory, they can
use the same names as functions in other directories. This is useful if you
want to create your own version of a particular function while retaining the
original in another directory. Because MATLAB looks for private functions
before standard M-file functions, it will find a private function named test.m
before a nonprivate M-file named test.m.
Primary functions and subfunctions can also be implemented as private
functions.
Private Directories
You can create your own private directories simply by creating subdirectories
called private using the standard procedures for creating directories or
folders on your computer. Do not place these private directories on your path.
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