Transform Linear Filter to System Identification "sys" object

I wish to create a System Identification Toolbox "sys" object so I can then calculate the time-domain step response. For example, how do I translate an "s-domain" butterworth filter to "sys" form:

[zb,pb,kb] = butter(8,2*pi*100e3,'s') ... or [b,a] = butter(8,2*pi*100e3,'s')

Answer 1

[Abel Babu]

System Identification Toolbox do not have a "sys" object per say but they do have "iddata" object that might do the trick for you, check out this documentation describing the " idfilt " function, that creates filter that are of iddata object:

https://in.mathworks.com/help/ident/ref/idfilt.html

After obtaining the object you can use the " step" function to get the time domain respons:

https://in.mathworks.com/help/ident/ref/step.html

Abel