sdr.FIR.impulse_response(N: int | None = None) → NDArray Returns the impulse response h[n] of the FIR filter. The impulse response h[n] is the filter output when the input is an impulse δ[n]. Parameters:¶ N: int | None = None¶The number of samples to return. The default is the filter length. Returns:¶ The impulse response of the IIR filter h[n]. See also sdr.plot.impulse_response Examples¶ See the FIR filters example.