MATLAB Programming Fundamentals - MathWorks

Handle Input Specification Changes

This example shows how to control the input specifications for a System object. You can

control what happens when an input specification changes.

You can also restrict whether the input complexity, data type, or size can change while the

object is in use. Whichever aspects you restrict cannot change until after the user calls

release.

React to Input Specification Changes

To modify the System object algorithm or properties when the input changes size, data

type, or complexity, implement the processInputSpecificationChangeImpl method.

Specify actions to take when the input specification changes between calls to the System

object.

In this example, processInputSpecificationChangeImpl changes the isComplex

property when either input is complex.

properties(Access = private, Logical)

isComplex = false;

end

methods (Access = protected)

function processInputSpecificationChangeImpl(obj,input1,input2)

if(isreal(input1) && isreal(input2))

obj.isComplex = false;

else

obj.isComplex = true;

end

end

end

Restrict Input Specification Changes

To specify that the input complexity, data type, and size cannot change while the System

object is in use, implement the isInputComplexityMutableImpl,

isInputDataTypeMutableImpl, and isInputSizeMutableImpl methods to return

false. If you want to restrict only some aspects of the System object input, you can

include only one or two of these methods.

34 System object Usage and Authoring