MATLAB Programming

9 Classes and Objects
Class Method
class constructor
display
set and get
subsref and
subsasgn
end
subsindex
converters like
double and char
Description
Creates an object of the class.
Called whenever MATLAB displays the contents
of an object (e.g., when an expression is entered
without terminating with a semicolon).
Accesses class properties.
Enables indexed reference and assignment for user
objects.
Supports end syntax in indexing expressions using
an object; e.g., A(1:end).
Supports using an object in indexing expressions.
Methods that convert an object to a MATLAB data
type.
The following sections discuss the implementation of each type of method, as
well as providing references to examples used in this chapter.
The Class Constructor Method
The @ directory for a particular class must contain an M-file known as the
constructor for that class. The name of the constructor is the same as the
name of the directory (excluding the @ prefix and .m extension) that defines
the name of the class. The constructor creates the object by initializing the
data structure and instantiating an object of the class.
Guidelines for Writing a Constructor
Class constructors must perform certain functions so that objects behave
correctly in the MATLAB environment. In general, a class constructor must
handle three possible combinations of input arguments:
• No input arguments
• An object of the same class as an input argument
• The input arguments used to create an object of the class (typically data of
some kind)
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