Sizes of output ports
[sz_1,sz_2,...,sz_n] = getOutputSizeImpl(obj)
[sz_1,sz_2,...,sz_n] = getOutputSizeImpl(obj) returns the sizes of each output port. The number of outputs must match the value returned from the getNumOutputs method or the number of output arguments listed in the step method.
For System objects with one input and one output and where you want the input and output sizes to be the same, you do not need to implement this method. In this case getOutputSizeImpl assumes the input and output sizes are the same and returns the size of the input. For variable-size inputs, the output size is the maximum input size.
If your System object has more than one input or output or you need the output and input sizes to be different, you must implement the getOutputSizeImpl method to define the output size. You also must use the propagatedInputSize method if the output size differs from the input size.
During Simulink® model compilation and propagation, the MATLAB System block calls the getOutputSize method, which then calls the getOutputSizeImpl method to determine the output size.