MATLAB Programming

9 Classes and Objects
Multiple Inheritance
In the multiple inheritance case, a class of objects inherits attributes from
more than one base class. The derived class object gets fields from all the base
classes, as well as fields of its own.
Multiple inheritance can encompass more than one generation. For example,
each of the base class objects could have inherited fields from multiple
base class objects, and so on. Multiple inheritance is implemented in the
constructors by callingclass with more than three arguments.
obj = class(structure,'classname',baseclass1,baseclass2,...)
You can append as many base class arguments as desired to the class input
list.
Nonunique Method Names in Base Classes
Multiple base classes can have associated methods of the same name. In this
case, MATLAB calls the method associated with the base class that appears
first in the class function call in the constructor function. There is no way to
access subsequent base class functions of this name.
Aggregation
In addition to standard inheritance, MATLAB objects support containment or
aggregation. That is, one object can contain (embed) another object as one of
its fields. For example, a rational object might use two polynom objects, one
for the numerator and one for the denominator.
You can call a method for the contained object only from within a method
for the outer object. When determining which version of a function to call,
MATLAB considers only the outermost containing class of the objects passed
as arguments; the classes of any contained objects are ignored.
See “Example — The Portfolio Container” on page 9-58 for an example of
aggregation.
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