Scilab Website | Contribute with GitLab | Mailing list archives | ATOMS toolboxes
Scilab Online Help
2023.0.0 - Русский


frfit

frequency response fit

Syntax

sys=frfit(w,fresp,order)
[num,den]=frfit(w,fresp,order)
sys=frfit(w,fresp,order,weight)
[num,den]=frfit(w,fresp,order,weight)

Arguments

w

positive real vector of frequencies (Hz)

fresp

complex vector of frequency responses (same size as w)

order

integer (required order, degree of den)

weight

positive real vector (default value ones(w)).

num,den

stable polynomials

Description

sys=frfit(w,fresp,order,weight) returns a bi-stable transfer function G(s)=sys=num/den, of of given order such that its frequency response G(w(i)) matches fresp(i), i.e. freq(num,den,%i*w) should be close to fresp. weight(i) is the weight given to w(i).

Examples

w=0.01:0.01:2;
s=poly(0,'s');
G=syslin('c',2*(s.^2+0.1*s+2), (s.^2+s+1)*(s.^2+0.3*s+1));
fresp=repfreq(G,w);
Gid=frfit(w,fresp,4);
frespfit=repfreq(Gid,w);
bode(w,[fresp;frespfit])

See also

  • frep2tf — transfer function realization from frequency response
  • factors — factorization in ℝ of a polynomial or a rational fraction
  • cepstrum — cepstrum calculation
  • mrfit — frequency response fit
  • freq — frequency response
  • calfrq — frequency response discretization
Report an issue
<< Identification Identification lattn >>

Copyright (c) 2022-2024 (Dassault Systèmes)
Copyright (c) 2017-2022 (ESI Group)
Copyright (c) 2011-2017 (Scilab Enterprises)
Copyright (c) 1989-2012 (INRIA)
Copyright (c) 1989-2007 (ENPC)
with contributors
Last updated:
Tue Mar 07 09:28:46 CET 2023