MATLAB: Resid command and treatment of iddata

Question

Hello all,

I have been struggling for hours, and I do not seem to get a very simple thing…

I use the command resid in order to obtain residuals from predictions of an AR model I already estimated using the ar command. I see that I can plot these residuals, but how can I actually obtain them in a vector, in order to be able to use them somewhere else? In general, how can I get, better transform, iddata into "normal" form?

Thanks

Kyriacos

Answer 1

If you did

>>e=resid(model,data);

then all you do to get the residuals as a vector is

>>resid_vector=e.y;

In general to access idatada signal just do

>>data.u

>>data.y

See doc iddata for more details.

HTH. Arkadiy