# scipy.signal.bilinear_zpk¶

scipy.signal.bilinear_zpk(z, p, k, fs)[source]

Return a digital IIR filter from an analog one using a bilinear transform.

Transform a set of poles and zeros from the analog s-plane to the digital z-plane using Tustin’s method, which substitutes (z-1) / (z+1) for s, maintaining the shape of the frequency response.

Parameters: z : array_like Zeros of the analog filter transfer function. p : array_like Poles of the analog filter transfer function. k : float System gain of the analog filter transfer function. fs : float Sample rate, as ordinary frequency (e.g. hertz). No prewarping is done in this function. z : ndarray Zeros of the transformed digital filter transfer function. p : ndarray Poles of the transformed digital filter transfer function. k : float System gain of the transformed digital filter.

Notes

New in version 1.1.0.

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