If the input signal has length L samples, impulse repsonse has length M samples, entering these L samples to FIR filter using conv function, will get L+M-1 output samples, while entering these L samples to FIR fitler, the output has L samples only instead of L+M-1 samples . Also, I'd like to know which L samples does FIR filter choose from L+M-1 samples (total samples) to be its output ?.

# MATLAB: FIR filter has output of same length as its input

convolutiondspfilter

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