# How do I make my variables save from my function?

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Sarah Johnson on 19 Feb 2020
Commented: Sarah Johnson on 19 Feb 2020
I have written a function function [f, grad, gradTwo] = Rosen(x), which returns the Rosenbrock function value f(x) to f, its gradient vector ∇f(x) to grad, and its Hessian matrix ∇ f(x) to gradTwo, at the given input point x and verify the function returns correct values.
I have written a function that does so, using x = [1, 1], but my values don't store.
g = @(x)100*(x(2) - x(1)^2)^2 + (1 - x(1))^2;
f = g(x);
gradTwo = [800*x(1)+2, -400*x(1); -400*x(2), 200];
end
Then my output when I run this is:
ans =
0
I believe my professor wants it to look like this:
f =
0
0
0
802 -400
-400 200
Is there a way to accomplish this? Any advice would be great, I'm not that great at MATLAB

Hiro Yoshino on 19 Feb 2020
You're doing well!
Try this:
x = [1 1];
You should prepare the three variables that recieve the calculus!

#### 1 Comment

Sarah Johnson on 19 Feb 2020
Thank you so much!!