Documentation of iduiqs

Global Index (short | long) | Local contents | Local Index (short | long)

Function Synopsis

iduiqs

Help text

IDUIQS Quickstart operation for ident.
      For the current Estimation data set, the impulse response(s)
      are calculated using correlation analysis. Then
      the frequency response(s) are calculated using spectral
      analysis. The delay in the different channels are
      estimated by picking the first value where the impulse
      response estimate exceeds 0.5*the estimated standard
      deviation. Then a fourth order ARX-model is computed
      with these delays. The step responses, the frequency
      responses and a compare view are opened for the resulting
      models

Cross-Reference Information

Listing of function iduiqs

function iduiqs

%   L. Ljung 4-4-94
%   Copyright (c) 1986-98 by The MathWorks, Inc.
%   $Revision: 3.4 $  $Date: 1997/12/02 03:41:05 $

global XIDplotw
[dum,info]=iduigetd('e');
Ncap=eval(info(4,:));
nuseq=eval(['[',info(7,:),']']);
nyseq=eval(['[',info(6,:),']']);
if ~isempty(nuseq),nu1=nuseq(1);else nu1=0;end
ny1=nyseq(1);
[ny,nu]=iduiiono('old',info,'dat');
chan_flag=0;
if nu>0
   if nu1>1|ny1>1,chan_flag=1;end
else
   if ny1>1,chan_flag=1;end
end
if nu>0
  IR=iduinpar('cra');
  for ky=1:ny
   for ku=1:nu
     kdum=find(IR(3:length(IR),(ky-1)*nu+ku)>IR(2)/2.58/2);
     if isempty(kdum)
        nk(ky,ku)=0;
     else
        nk(ky,ku)=kdum(1)-1;
     end
   end
  end
  set(XIDplotw(5,2),'value',1),iduipw(5);
  if chan_flag,iduiiono('update',ny1,nu1,5,1);end
end
iduinpar('spa');
if nu>0,
  wino=2;
else
  wino=7;
end
set(XIDplotw(wino,2),'value',1),iduipw(wino);
if chan_flag,iduiiono('update',ny1,nu1,wino,1);end
iduistat('Computing a 4th order ARX model...');
if nu==0,nk=zeros(ny,nu);end
iduiarx('estimate',[4*ones(ny,ny),4*ones(ny,nu),nk],'arxqs');
set(XIDplotw(3,2),'value',1),iduipw(3);
if ny1>1,iduiiono('update',ny1,nu1,3,1);end
if Ncap>19*ny+30*(nu+1)
  iduistat('Computing a default order state space model using N4SID...');
  iduiss('qsestimate');
else
  iduistat('Too few data points for default order N4SID model.')
end