Inverse Laplace and plotting system respone

Hello, I am having some issues with plotting function I get from inverse Laplace transformation. It is a linear controlling system with input step signal.

syms s

A = 1+1/(103*s);
B = (0.33/s)/(1-0.33/s);
C = 0.0875/s;

n = A*B*C;
d = 1 - (A*B*C);
r = 1/s; %step function

tf = (n/d)*r

h = ilaplace(tf)

ezplot(h, [1,1000]), axis square, grid on

This is what i get.

tf =

-(231*(1/(103*s) + 1))/(8000*s^3*((231*(1/(103*s) + 1))/(8000*s^2*(33/(100*s) - 1)) + 1)*(33/(100*s) - 1))

h =

- 8240*sum(-(33*r3*exp(r3*t) - 100*r3^2*exp(r3*t))/(- 2472000*r3^2 + 543840*r3 + 23793), r3 in RootOf(s3^3 - (33*s3^2)/100 - (231*s3)/8000 - 231/824000, s3)) - 1

??? Error using ==> char
Cell elements must be character arrays.

Error in ==> ezplot at 158
      fmsg = char(f);

Error in ==> sym.ezplot at 56
      h = ezplot(char(f),varargin{:});

Error in ==> laplace2 at 26
ezplot(h, [1,1000]), axis square, grid on 
>>

Can please someone help me with that? I have to plot the system response.

Thanks.

Answer 1

[Walter Roberson]

Try

ezplot(matlabFunction(h), [1,1000])

or just

t = linspace(1,1000,500);   %500 is number of samples to plot
hfun = matlabFunction(h);
plot(t, hfun(t));