Static Methods

What Are Static Methods

Static methods are associated with a class, but not with specific instances of that class. These methods do not require an object of the class as an input argument. Therefore, you can call static methods without creating an object of the class.

Why Define Static Methods

Static methods are useful when you do not want to create an instance of the class before executing some code. For example, suppose you want to set up the MATLAB^® environment or use the static method to calculate data required to create class instances.

Suppose that a class needs a value for pi calculated to particular tolerances. The class could define its own version of the built-in pi function for use within the class. This approach maintains the encapsulation of the class's internal workings, but does not require an instance of the class to return a value.

Defining Static Methods

To define a method as static, set the methods block Static attribute to true. For example:

classdef MyClass
   methods(Static)
       function p = pi(tol)
           [n d] = rat(pi,tol);
           p = n/d;
       end
   end
end

Calling Static Methods

Invoke static methods using the name of the class followed by dot (.), then the name of the method:

classname.staticMethodName(args,...)

Calling the pi method of MyClass in the previous section would require this statement:

value = MyClass.pi(.001);

You can also invoke static methods using an instance of the class, like any method:

obj = MyClass;
value = obj.pi(.001);

Inheriting Static Methods

Subclasses can redefine static methods unless the method's Sealed attribute is also set to true in the superclass.