transfer function doesn't work

hello everyone, I want to solve and plot the step response of this model, the strength of the impulse is 5 and the step input is 5 too. the file doesn't work!

as you see below

matlab knows the transform function, so what was the error ?

Answer 1

[Adam]

We can't see the full error message.

Type

which tf -all

to see if Matlab really knows about the function. I suspect from the tail end of your error message that you don't have the signal processing toolbox in which it lives.

Answer 2

[Muhammed Fasil]

Its working. I used same code without any change. Try in some other matlab version. Find the attachment

[lounis chehrit]

Just a question is It normal to have a transfer function like this ?

It's definied by :

Real(TF(v)) = cos(2*pi*v).

and phase is 0.

I thing that the parameter s=j*w.

So is It normal to have a real part like this? ( parameter in the cosine)

and how to get transfert function from real and image parts.