Find the Jacobian of a matrix

I have a symbolic 3x2 matrix call it fx and I would like to find the derivatives of that matrix with respect to two variables. Which means I will get 2 3x2 matrices where the first matrix is a 3x2 is the derivatives with respect to the first variable and the second matrix is the derivative with respect to the second variable, so a 3x2x2 matrix.

Assume x = [a,b] and I am doing jacobian(fx, x), yet fx has to be a vector or a scalar. I tried reshape as well, and it also did not work.

Thank you for your time.

Answer 1

[bio lim]

I don't think that would be called " Jacobian matrix " anymore.

What if you do it like this?

syms a b
yourMat = [a*a b+a;
           b^2 a^2+b^2;
           a b];

newMat{1} = diff(yourMat, a);
newMat{2} = diff(yourMat, b);

Output:

>> newMat{1}

ans =

[ 2*a,   1]
[   0, 2*a]
[   1,   0]

>> newMat{2}

ans =

[   0,   1]
[ 2*b, 2*b]
[   0,   1]