Error in equation/variables

I'm facing a small problem in MATLAB, this code I wrote is not running due to an error in line 11 (the first equation in the image attached below).

I am not sure if i should write a0 in global or not, a0 is constant and equals 1.

How can I fix this error?

here is the code

and these are the errors

[Afnan Mussa]

Thank you all.

I am still having an error in teh dispaly figure line

Answer 1

[Image Analyst]

Theta is a vector so you need to decide if you want to do Theta(1)^2, Theta(2)^2 or Theta.^2 (using a dot).

[Christopher McCausland]

I agree with @Image Analyst and those below, Theta is the issue not a0. Here is the documentation to explain it a bit more. Look at the . (dot) operator for element wise operations.

[Afnan Mussa]

I got it. Thank you.

[Image Analyst]

And next time, if you post actual code rather than an image of it, we can fix it for you.

Answer 2

[Sulaymon Eshkabilov]

% You need to perform elementwise operation. Since Theta = [0, 120]
Theta^2  % must be
Theta.^2
.        % missing before / operator

Good luck

[Afnan Mussa]

Thank you.

Answer 3

[Jacob Forbes]

Writing a0 into global shouldn't be your issue as you said it is a constant and you have it defined as 1. From what I see, the problem you're running into is you are trying to take the square of a vector (Theta) which cannot be done unless it is done element by element, in which case you would use the operator ".^2" after (Theta) instead of "(Theta)^2" like you currently have written.

[Afnan Mussa]

Thank you.