What is the code to do a transfer function between input and output?

I've got 2 vectors. I've to do the trasnsfer function between them. What is the code that I have to use?

Answer 1

[Azzi Abdelmalek]

N=[1 2]
D=[1 3 4]
model=tf(N,D)  % for continuous system

ts=0.1;
modeld=tf(N,D,ts)% for discrete system

[Azzi Abdelmalek]

[max commented]

Ok, I've wrong. I need the code inside the tf. I would like to kwnow how matlab calculate the transfer function.

[Azzi Abdelmalek]

max, don't answer your question when you need to post a comment. Also you have 23 questions asked, none of them are accepted, sometimes you did not reply to the members answers neither their comments

Answer 2

[Azzi Abdelmalek]

You can use this code

syms p
N=[1 2]
D=[1 3 4]
moel=sum(N.*p.^(numel(N)-1:-1:0))/sum(D.*p.^(numel(D)-1:-1:0))