Changing a parameter in a trasferire function

I have the following transfer function

h = 1 for t<=0 and 0 for t>0

I have to determine the properties of the LTI system for t<=0 and t>0.

How can I make h change its value automatically ? Without doing two cases for h=1 and h=0

Thank you for your help

[Paul]

Hi Gaetano,

Assuming t is the independent variable of the the inverse transform of G(s), i.e., g(t) -> G(s), the coefficients in G(s) can't change as a function of time. LTI systems have constant coefficients. Can you clarify what t is how it enters into the problem?

Answer 1

[Star Strider]

I demonstrated this in your earlier post: How to change a parameter in a model.

The same approach applies here —

s = tf('s');
G = @(h) s^2 / ((s+h)*(s+1));
t = [linspace(0, 10, 250); linspace(-10, 0, 250)];

figure
for k = 1:2
    subplot(2,1,k)
    step(G(k-1),t(k,:))
    grid
    title(sprintf('h = %d',k-1))
end

The function is not defined for t<0.

.

[Gaetano Ruocco]

Thank you so much

[Star Strider]

As always, my pleasure!