use filtfilt with error of Not enough input arguments

13 vues (au cours des 30 derniers jours)
Miao
Miao le 30 Juil 2014
Commenté : Honglei Chen le 30 Juil 2014
Hi all: I used fdatool designed a bandpass filter 'bp521',to filter my signal 'SINGAL', the main contents of the filter are below:
function Hd = bp521
% All frequency values are in kHz.
Fs = 90; % Sampling Frequency
Fstop1 = 3.5; % First Stopband Frequency
Fpass1 = 5.5; % First Passband Frequency
Fpass2 = 21; % Second Passband Frequency
Fstop2 = 23; % Second Stopband Frequency
Dstop1 = 0.001; % First Stopband Attenuation
Dpass = 0.057501127785; % Passband Ripple
Dstop2 = 0.0001; % Second Stopband Attenuation
flag = 'scale'; % Sampling Flag
% Calculate the order from the parameters using KAISERORD.
[N,Wn,BETA,TYPE] = kaiserord([Fstop1 Fpass1 Fpass2 Fstop2]/(Fs/2), [0 ...
1 0], [Dstop1 Dpass Dstop2]);
% Calculate the coefficients using the FIR1 function.
b = fir1(N, Wn, TYPE, kaiser(N+1, BETA), flag);
Hd = dfilt.dffir(b);
I can use filter(bp521,SIGNAL), but when I want to use it by filtfilt, it always gave error: 'Not enough input arguments.', so I wonder why?? could there anyone help me with this?
Thank you in advance!
  1 commentaire
Star Strider
Star Strider le 30 Juil 2014
Include your call to filtfilt in the code you post.

Connectez-vous pour commenter.

Connectez-vous pour répondre à cette question.

Réponses (1)

Honglei Chen
Honglei Chen le 30 Juil 2014
You can do the following:
bp521Coeff = coeffs(bp521);
filtfilt(bp521Coeff.Numerator,bp521Coeff.Denominator,SIGNAL)
  2 commentaires
Miao
Miao le 30 Juil 2014
Thank you very much for your help, I tried, the bp521Coeff is a 1*1 struct, but there are nothing in bp521Coeff.Denominator?
Honglei Chen
Honglei Chen le 30 Juil 2014
oh, it's an FIR, so you just do
filtfilt(bp521Coeff.Numerator,1,SIGNAL)

Connectez-vous pour commenter.

Catégories

En savoir plus sur Digital Filtering dans Help Center et File Exchange

Tags

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by