`scipy.signal._filter_design:cheb1ap`

Signature

def cheb1ap(N, rp, *, xp = None, device = None)

Return (z,p,k) for Nth-order Chebyshev type I analog lowpass filter.

The returned filter prototype has rp decibels of ripple in the passband.

The filter's angular (e.g. rad/s) cutoff frequency is normalized to 1, defined as the point at which the gain first drops below -rp.

N : int: The order of the filter
rp : float: The ripple intensity
xp : array_namespace, optional: Optional array namespace. Should be compatible with the array API standard, or supported by array-api-compat. Default: numpy
device : any: optional device specification for output. Should match one of the supported device specification in xp.

z : ndarray[float64]: Zeros of the transfer function. Is always an empty array.
p : ndarray[complex128]: Poles of the transfer function.
k : float: Gain of the transfer function.