gsignal (version 0.3-7)

cheb2ap: Chebyshev Type II filter prototype

Description

Return the poles and gain of an analog Chebyshev Type II lowpass filter prototype.

Usage

cheb2ap(n, Rs)

Value

list of class Zpg containing poles and gain of the filter

Arguments

n

Order of the filter.

Rs

dB of stop-band ripple.

Author

Carne Draug, .
Conversion to R by Geert van Boxtel, .

Details

This function exists for compatibility with 'Matlab' and 'Octave' only, and is equivalent to cheby2(n, Rp, 1, "low", "s").

Examples

## 9th order Chebyshev type II low-pass analog filter
zp <- cheb2ap(9, 30)
w <- seq(0, 4, length.out = 128)
freqs(zp, w)