# Thread: Basic MATLAB questions

1. ## Basic MATLAB questions

1.If I am given a transfer function in factorized form e.g (s+1)(s+2)/(s+2j)(s-2j)(s+3) then by which command or set of commands can I get it converted into the polynomial form like A(s)/B(s) ?

2. How can I find characteristic equation of the above example? Like its a polynomial fraction so how do I handle it ?

2. Originally Posted by Altair
1.If I am given a transfer function in factorized form e.g (s+1)(s+2)/(s+2j)(s-2j)(s+3) then by which command or set of commands can I get it converted into the polynomial form like A(s)/B(s) ?

2. How can I find characteristic equation of the above example? Like its a polynomial fraction so how do I handle it ?
This is not a question about matlab, but about the symbolic toolbox which is a fronm end to the Maple engine.

Google for "matlab symbolic toolbox help" then look at the hits, the first one is the Matlab documentation for the toolbox.

CB

3. And where do I go from there ? I thought tha like 'roots' gives roots of the polynomial so something like that could be done in inverse...please explain...

4. Actually I am new to MATLAB and I want to know te exact steps in finding a characteristic equation...