errors on function vs time plot

Hi, I am trying to make a function vs time plot of v = 12e^(-8t) vs time using t =linspace(-1,1,100) (i also wasnt sure what parameters to use for the linspace funcation) where v = 0 when t is less then 00. But when i try to run the code it says there is an error in my v(t) equation line. I have't used MATHLAB a lot so im not sure if its a sytax issue or something else. This is my code. Thanks for any help!

system v(t)

t = linspace(-1,1,100); 
v(t) = 12.*e^-8.*t;


if t < 0
    v(t) = 0;

plot(v(t), t);
end

[Laila]

I have also tried using exp(1) instead of e but still no luck.

Answer 1

[Torsten]

t = linspace(-1,1,100); 
v = 12*exp(-8*t).*(t>=0);
plot(t,v)

[Laila]

thank you!

Answer 2

[Star Strider]

The exponential function in MATLAB (and every other programming language I have encountered) is exp.

Try something like this —

t = linspace(-1,1,100); 
v = @(t) 12.*exp(-8.*t);

vt = v(t);
vt(t < 0) = 0;

figure
plot(t, vt);

.

[Laila]

thank you!

[Star Strider]

My pleasure!