MATLAB Object-Oriented Programming

Which Kind of Class to Use

In this section...

“Examples of Value and Handle Classes” on page 7-11

“When to Use Value Classes” on page 7-11

“When to Use Handle Classes” on page 7-12

Examples of Value and Handle Classes

Handle and value classes are useful in different situations. For example, value classes

enable you to create new array classes that have the same behavior as MATLAB numeric

classes.

“Representing Polynomials with Classes” on page 19-2 and “Representing Structured

Data with Classes” on page 3-19 provides examples of value classes.

Handle classes enable you to create objects that more than one function or object can

share. Handle objects allow more complex interactions among objects because they allow

objects to reference each other.

“Implementing Linked Lists with Classes” on page 3-31 and “Developing Classes —

Typical Workflow” on page 3-8 provides examples of a handle class.

When to Use Value Classes

Value class objects behave like normal MATLAB variables. A typical use of value classes is

to define data structures. For example, suppose that you want to define a class to

represent polynomials. This class can define a property to contain a list of coefficients for

the polynomial. It can implement methods that enable you to perform various operations

on the polynomial object. For example, implement addition and multiplication without

converting the object to another class.

A value class is suitable because you can copy a polynomial object and have two objects

that are identical representations of the same polynomial. For an example of value

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

For information on MATLAB pass-by-value semantics, see “Avoid Unnecessary Copies of

Data”.

Value or Handle Class — Which to Use