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.
Static methods are useful when you do not want to create an instance of the class before executing some code. For example, you might 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.
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
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);
Subclasses can redefine static methods unless the method's Sealed
attribute
is also set to true
in the superclass.