scipy.signal.cheby1¶
- scipy.signal.cheby1(N, rp, Wn, btype='low', analog=False, output='ba')[source]¶
Chebyshev type I digital and analog filter design.
Design an Nth order digital or analog Chebyshev type I filter and return the filter coefficients in (B,A) or (Z,P,K) form.
Parameters : N : int
The order of the filter.
rp : float
Provides the maximum ripple in the passband. (dB)
Wn : array_like
A scalar or length-2 sequence giving the critical frequencies. For digital filters, Wn is normalized from 0 to 1, where 1 is the Nyquist frequency, pi radians / sample. (Wn is thus in half-cycles / sample.) For analog filters, Wn is in radians / second.
btype : {‘lowpass’, ‘highpass’, ‘bandpass’, ‘bandstop’}, optional
The type of filter. Default is ‘lowpass’.
analog : bool, optional
When True, return an analog filter, otherwise a digital filter is returned.
output : {‘ba’, ‘zpk’}, optional
Type of output: numerator/denominator (‘ba’) or pole-zero (‘zpk’). Default is ‘ba’.
Returns : b, a : ndarray, ndarray
Numerator (b) and denominator (a) polynomials of the IIR filter. Only returned if output='ba'.
z, p, k : ndarray, ndarray, float
Zeros, poles, and system gain of the IIR filter transfer function. Only returned if output='zpk'.
See also
