this is maximize (omega-(sigma*(trace(W+V))+mm*ID) )

variable W(mm,mm) semidefinite V(mm,mm) semidefinite lamda0

sigma ID

I don’t understand what the problem is. I hope you can help me .

The error statement prompt is the object function

That usually means CVX scalar or matrix variables (expressions) are being multiplied. Is `sigma`

a variable (it’s not clear from your not properly formatted out of order code extract… If so it is multiplying elements of `W`

via trace. From this extract, it is not obvious there is any repair to the apparent non-convexity, other than requiring `sigma `

to be input data rather than a CVX variable.

Thank you very much , Mark.

But when I set sigma to be input data, I get this error message: Your objective function is not a scalar. Why is it so?

I don’t know. Perhaps `omega`

is not a scalar?

OK. Thank you, Mark. I’ll look into it more carefully