Plots the impulse response \(h[n]\) of a filter.

The impulse response \(h[n]\) is the filter output when the input is an impulse \(\delta[n]\).

Parameters:¶

filter: FIR | IIR | ArrayLike | tuple[ArrayLike, ArrayLike]¶

The filter definition.

• sdr.FIR, sdr.IIR: The filter object.

• npt.ArrayLike: The feedforward coefficients \(b_i\).

• tuple[npt.ArrayLike, npt.ArrayLike]: The feedforward coefficients \(b_i\) and feedback coefficients \(a_j\).

N: int | None = None¶

The number of samples \(N\) to plot. If None, the length of b is used for FIR filters and 100 for IIR filters.

offset: float = 0.0¶

The x-axis offset to apply to the first sample. Can be useful for comparing the impulse response of filters with different lengths.

ax: plt.Axes | None = None¶

The axis to plot on. If None, the current axis is used.

type: 'plot' | 'stem' = 'stem'¶

The type of plot to use.

**kwargs¶

Additional keyword arguments to pass to the plotting function.

Examples¶

See the FIR filters example.

In [1]: h_srrc = sdr.root_raised_cosine(0.5, 10, 10)

In [2]: plt.figure(); \
   ...: sdr.plot.impulse_response(h_srrc)
   ...: 

See the IIR filters example.

In [3]: zero = 0.6; \
   ...: pole = 0.8 * np.exp(1j * np.pi / 8); \
   ...: iir = sdr.IIR.ZerosPoles([zero], [pole, pole.conj()])
   ...: 

In [4]: plt.figure(); \
   ...: sdr.plot.impulse_response(iir, N=30)
   ...: