MATLAB Programming Fundamentals - MathWorks

System Object Functions

After you create a System object, you use various object functions to process data or

obtain information from or about the object. The syntax for using functions is <object

function name>(<system object name>), plus possible extra input arguments. For

example, for txfourier = dsp.FFT, where txfourier is a name you assign, you call

the reset function using reset(txfourier).

Common Object Functions

All System objects support the following object functions. In cases where a function is not

applicable to a particular object, calling that function has no effect on the object.

Function Description

Run the object function,

or

step

Runs the object to process data using the algorithm defined by

that object.

Example: For the object dft = dsp.FFT;, run the object via:

• y = dft(x)


• y = step(dft,x)

As part of this processing, the object initializes resources,

returns outputs, and updates the object states as necessary.

During execution, you can change only tunable properties. Both

ways of running a System object return regular MATLAB

variables.

release Release resources and allow changes to System object property

values and additional characteristics that are limited while the

System object is in use.

reset Resets the System object to the initial values for that object.

nargin Returns the number of inputs accepted by the System object

algorithm definition. If the algorithm definition includes

varargin, the nargin output is negative.

nargout Returns the number of outputs accepted by the System object

algorithm definition. If the algorithm definition includes

varargout, the nargout output is negative.

34 System object Usage and Authoring