Calculating gradient of f in point A?

Hello! I am trying to calculate the gradient of a function in a point, but I can't seem to do it.

I have calculated the gradient through the functions diff and gradient. Now I am trying to replace x1 and x2 by 5 and 6, respectively, to calculate the gradient in this point (called A) through any of the gradient functions, but MATLAB does not allow it.

Any help? Thanks in advance!

syms x1 x2
f = x1 + x2^2;
A = [5, 6];
f_grad_diff = [diff(f, x1), diff(f, x2)];
f_grad_gradient = gradient(f);

Answer 1

[Star Strider]

Create them as functions —

syms x1 x2
f = x1 + x2^2;
A = [5, 6];
f_grad_diff(x1,x2) = [diff(f, x1), diff(f, x2)];
f_grad_gradient(x1,x2) = gradient(f);

x1s = sym(5);
x2s = sym(6);

diff_evaluated = f_grad_diff(x1s,x2s)

diff_evaluated = 

gradient_evaluated = f_grad_gradient(x1s,x2s)

gradient_evaluated = 

The jacobian function is also an option.)

Are these the desired results?

.

[ABCDEFG HIJKLMN]

These are exactly the desired results. Thank you!

[Star Strider]

As always, my pleasure!

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