Difference between fvtool and freqz
10 Ansichten (letzte 30 Tage)
Ältere Kommentare anzeigen
Daoyuan
am 27 Feb. 2014
Kommentiert: Reza Ghorbani
am 18 Jan. 2019
Hi,
I am currently using a few notch filters, however a lot of the time I notice different results depending on if I am using freqz or fvtool to plot (eg. the magnitude of fvtool is 10 times or twice that of freqz), I don't seem to understand what is wrong with my code, or if there is any difference between how the magnitude is calculated. code: %======================
close all;
clear all;
wo = 60/(1000/2); bw = wo/35;
[b,a] = iirnotch(wo,bw);
fvtool(b, a);
freqz(b, a);
%======================
Thank you.
0 Kommentare
Akzeptierte Antwort
Honglei Chen
am 3 Mär. 2014
There is really not much difference between the two. If you are referring to the differences between the null depths, it is because the two use different default values of FFT points. The default of freqz is a 512-point FFT while for fvtool, it's 8192 points. If you use
freqz(b,a,8192)
You should see similar results.
HTH
1 Kommentar
Weitere Antworten (0)
Siehe auch
Kategorien
Mehr zu Filter Design finden Sie in Help Center und File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!