Code wont work keeps giving error message: Argument to dynamic structure reference must evaluate to a valid field name.

this is my code:

t=0:0.001:10; wn= 0.898; a= 0.843; z= 0.005122; wd=0.897;

y= a*(exp.(-z*wn*t))*(sin(wd*t)) and I keep getting the same error message can someone help please thanks

Answer 1

[Jan]

In "exp.(-z*wn*t)" the term "exp" is treated as a struct and "(-z*wn*t)" as a field name. "S.(name)" is a reference by a dynamic field name, when S is a struct and name a string.

Most likely you want:

y = a * exp(-z * wn * t) * sin(wd * t);

Answer 2

[Star Strider]

Put the ‘dot operator’ here instead:

y = a*(exp(-z*wn*t)) .* (sin(wd*t))
                     ↑

That will do the element-wise multiplication you intend.