How to get a Scalar from a Matrix and Two Vectors

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If I am given a 3x3 matrix A and two 3x1 vectors X,Y I basically need to multiply them out with each other to get a scalar. My first attempt was
X'*A*Y
It could be due to the way that I have MATLAB set up, but if I do something like r'*r for two radial vectors it creates another vector rather than a scalar product, so in the example above I will just end up with a tensor when I really want a scalar ie. the matrix A has to multiply the vector on the right and then the transpose of the other vector on the left has to multiply the result to end up with a scalar.

Accepted Answer

madhan ravi
madhan ravi on 20 Jan 2019
Edited: madhan ravi on 20 Jan 2019
Why not the below two possible options?
X*(A*Y) % A - 3 X 3 matrix , X - 3 X 1 vector , Y - 3 X 1 vector
Y*(A*X)

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