Plotting Impulse response of a system and I am stuck

Hi, while I am practising about plotting impulse signal here and I'm stuck:

and I wanted to plot this signal:

I have the following array:

Answer 1

[Walter Roberson]

sympref('HeaviSideAtOrigin', 1);
 u = @heaviside

u = function_handle with value:
    @heaviside

 syms t
 h(t) = exp(-2*t) .* u(t-1);
 
fplot(h, [-5 5])

[cikalekli]

May I ask something to learn in a clear way please?

My question is I have't found yet the usage aim of sympref('HeaviSideAtOrigin', 1); line in your code. While I was reading about plotting impulse graphs in my book which is "Signals and Systems Using MATLAB by Luis F. Chaparro" there was nothing mentioned about in this way.

This is why, may I ask that is there any different demonstration instead of using this sympref code line please?

Thanks a lot in advance.

[Walter Roberson]

https://www.mathworks.com/help/symbolic/sympref.html#buoiz5o-2

There are different conventions for what the Heaviside function should return when the input value is exactly 0. The unit step function is the same as Heaviside with output value 1 when the input is 0.

[Walter Roberson]

See also https://www.mathworks.com/help/signal/gs/impulse-step-and-ramp-functions.html

[cikalekli]

I checked the link you sent.

In the link there was no usage of this line of code:

sympref('HeaviSideAtOrigin', 1);

u = @heaviside

Can you please tell me why have we used that code particulary in this example please?

You are life saver and I'd be really glad for your help for elaborating that.

[David Hill]

It was clearly in the link, heaviside(0) is default 1/2. Inorder to change this to 1, the code above is used.