scipy.signal.lp2hp_zpk#
- scipy.signal.lp2hp_zpk(z, p, k, wo=1.0)[source]#
Transform a lowpass filter prototype to a highpass filter.
Return an analog high-pass filter with cutoff frequency wo from an analog low-pass filter prototype with unity cutoff frequency, using zeros, poles, and gain (‘zpk’) representation.
- Parameters
- zarray_like
Zeros of the analog filter transfer function.
- parray_like
Poles of the analog filter transfer function.
- kfloat
System gain of the analog filter transfer function.
- wofloat
Desired cutoff, as angular frequency (e.g., rad/s). Defaults to no change.
- Returns
- zndarray
Zeros of the transformed high-pass filter transfer function.
- pndarray
Poles of the transformed high-pass filter transfer function.
- kfloat
System gain of the transformed high-pass filter.
Notes
This is derived from the s-plane substitution
\[s \rightarrow \frac{\omega_0}{s}\]This maintains symmetry of the lowpass and highpass responses on a logarithmic scale.
New in version 1.1.0.