How to get the transfer matrices for vector transformation?

I want to find a real entry square matrices to transfer one symbolic vector to another symbolic vector which in the form of A*x1=x2, A is a square matrices and x1, x2 are vectors. x1 and x2 are given and A is what I want to find. For example, x1=[f1;f2] and x2=-[f2;f2], then A=[0 -1;0 -1]. I'm not sure how to code it in MATLAB. Could anyone help me?

Answer 1

[Walter Roberson]

A = x2\x1;

The result will be

[ -f2/f1, 0]
[ -f2/f1, 0]

which is a valid solution. The transform matrix A is not unique.

[DmArcher]

but I want A be a matrices with all real number elements

[Walter Roberson]

That is not generally possible. It might be possible for a restricted set of possible transformations, such as if you are certain that x2 is a linear combination of the variables present in x1; there might also need to be restrictions on the forms of x1.