Is there any form to implement the matrix multiplied by its own conjugate transpose


(bloo) #1

There is a variable x(2,2) complex
I want to use xx’ in my function.
I only found sum_square_abs(x) to get the diagonal of x
x’.
It seems like there is no way to have the full x*x’
Any reformulation to get it out?
Thank you.


(Mark L. Stone) #2

Please provide a context for what you want to do. Is your problem actually convex, and if so, how have you determined that? This question will be marked non-convex, unless and until you show you are trying to do something convex.


(bloo) #3

I don’t have the context with me right now,I will try to prove it later
maybe I could simplify my question.
Can I run it somehow?

cvx_begin
variable x(2,2)
expression y
y=x*x'; %this is not allowed.is that means a matrix multiply its own transpose is an Nonconvex expression?
maximize y
subject to
x(:)<=1
cvx_end

(Mark L. Stone) #4

Forget about convexity or DCP rules for the moment. Your program doesn’t make any sense. Your objective function is a 2 by 2 matrix. Your objective function needs to be a real scalar. If you show us what your objective function really is, perhaps further advice can be provided.


(bloo) #5

Sorry,my mistake.
I will provide my object function next week.