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System object: dsp.FIRDecimator
Package: dsp

Decimate input by integer factor


Y = step(firdecim,X)



Starting in R2016b, instead of using the step method to perform the operation defined by the System object™, you can call the object with arguments, as if it were a function. For example, y = step(obj,x) and y = obj(x) perform equivalent operations.

Y = step(firdecim,X) outputs the filtered and downsampled values, Y, of the input signal, X. A Ki-by-N input matrix is treated as N independent channels. The length of each column must be a multiple of the DecimationFactor property value. The FIR decimator operates on each channel separately and generates a Ko-by-N output matrix where Ko = Ki/M with M the decimation factor. The object supports real and complex floating-point and fixed-point inputs, except for complex unsigned fixed-point inputs.


obj specifies the System object on which to run this step method.

The object performs an initialization the first time the step method is executed. This initialization locks nontunable properties (MATLAB) and input specifications, such as dimensions, complexity, and data type of the input data. If you change a nontunable property or an input specification, the System object issues an error. To change nontunable properties or inputs, you must first call the release method to unlock the object.

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