bundles / scipy latest / scipy / signal / _filter_design / lp2lp_zpk
function
scipy.signal._filter_design:lp2lp_zpk
Signature
def lp2lp_zpk ( z , p , k , wo = 1.0 ) Summary
Transform a lowpass filter prototype to a different frequency.
Extended Summary
Return an analog low-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
z: array_likeZeros of the analog filter transfer function.
p: array_likePoles of the analog filter transfer function.
k: floatSystem gain of the analog filter transfer function.
wo: floatDesired cutoff, as angular frequency (e.g., rad/s). Defaults to no change.
Returns
z: ndarrayZeros of the transformed low-pass filter transfer function.
p: ndarrayPoles of the transformed low-pass filter transfer function.
k: floatSystem gain of the transformed low-pass filter.
Notes
This is derived from the s-plane substitution
Array API Standard Support
lp2lp_zpk has experimental support for Python Array API Standard compatible backends in addition to NumPy. Please consider testing these features by setting an environment variable SCIPY_ARRAY_API=1 and providing CuPy, PyTorch, JAX, or Dask arrays as array arguments. The following combinations of backend and device (or other capability) are supported.
==================== ==================== ==================== Library CPU GPU ==================== ==================== ==================== NumPy ✅ n/a CuPy n/a ✅ PyTorch ✅ ✅ JAX ⚠️ no JIT ⛔ Dask ⚠️ computes graph n/a ==================== ==================== ====================
See
dev-arrayapifor more information.
Examples
Use the 'zpk' (Zero-Pole-Gain) representation of a lowpass filter to transform it to a new 'zpk' representation associated with a cutoff frequency wo.from scipy.signal import lp2lp_zpk z = [7, 2] p = [5, 13] k = 0.8 wo = 0.4✓
lp2lp_zpk(z, p, k, wo)
✗See also
Aliases
-
scipy.signal.lp2lp_zpk