MATLAB Object-Oriented Programming

Subclasses of Built-In Types with Properties

In this section...

“Specialized Numeric Types with Additional Data Storage” on page 12-68

“Subclasses with Properties” on page 12-68

“Property Added” on page 12-69

“Methods Implemented” on page 12-69

“Class Definition Code” on page 12-69

“Using ExtendDouble” on page 12-72

“Concatenation of ExtendDouble Objects” on page 12-75

Specialized Numeric Types with Additional Data Storage

Subclass built-in numeric types to create customized data types that inherit the

functionality of the built-in type. Add or modify functionality to that provided by the

superclass by implementing class methods.

Providing additional data storage in the subclass by defining properties can be a useful

extension to the built-in data class. However, the addition of properties to the subclass

requires the subclass to define methods to implement standard array behaviors.

For more information, see “Subclasses of MATLAB Built-In Types” on page 12-50.

Subclasses with Properties

When a subclass of a built-in class defines properties, default indexing and concatenation

do not work. The default subsref, subsasgn, horzcat, and vertcat functions cannot

work with unknown property types and values. Therefore, the subclass must define these

behaviors by implementing these methods.

This sample implementation of the ExtendDouble class derives from the double class

and defines a single property. The ExtendDouble class definition demonstrates how to

implement indexing and concatenation for subclasses of built-in classes

12 How to Build on Other Classes