Cannot perform the operation: {real affine} .* {convex}”

I would like to minimize this function
–where B is the matrix I need to optimize, B is a Hermitian matrix and R1 ,R2 are both the known matrix. I remember that trace_inv and trace are both convex problem. Howerer, I get the error that
” ??? Error using ==> cvx.times at 173
Disciplined convex programming error:
Cannot perform the operation: {real affine} .
So what is the problem?

FAQ: Why doesn’t CVX accept my problem? [READ THIS FIRST]

Thanks,mcg,but I read that before and I cannot get the answer,because I think it is convex. I am sorry about that.

Prove it is convex and we’ll work further to see if you can express it in a DCP-compliant manner. But I am almost certain it is not.

Ok, so how to transform it to convex problem? thanks very much.

I don’t know if it can.

Ok, thank you