MATLAB Programming

Classes and Objects: An Overview
Features of Object-Oriented Programming
When using well-designed classes, object-oriented programming can
significantly increase code reuse and make your programs easier to maintain
and extend. Programming with classes and objects differs from ordinary
structured programming in these important ways:
• Function and operator overloading. You can create methods that
override existing MATLAB functions. When you call a function with a
user-defined object as an argument, MATLAB first checks to see if there is
a method defined for the object’s class. If there is, MATLAB calls it, rather
than the normal MATLAB function.
• Encapsulation of data and methods. Object properties are not visible
from the command line; you can access them only with class methods.
This protects the object properties from operations that are not intended
for the object’s class.
• Inheritance. You can create class hierarchies of parent and child classes
in which the child class inherits data fields and methods from the parent. A
child class can inherit from one parent (single inheritance) ormanyparents
(multiple inheritance). Inheritance can span one or more generations.
Inheritance enables sharing common parent functions and enforcing
common behavior amongst all child classes.
• Aggregation. You can create classes using aggregation, inwhichanobject
contains other objects. This is appropriate when an object type is part
of another object type. For example, a savings account object might be a
part of a financial portfolio object.
MATLAB Data Class Hierarchy
All MATLAB data types are designed to function as classes in object-oriented
programming. The diagram below shows the fifteen fundamental data types
(or classes) defined in MATLAB. You can add new data types to MATLAB by
extending the class hierarchy.
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