How to let the condition that matrix is nonpositive definite be one of the constraints in CVX

How to let the condition that matrix is nonpositive definite be one of the constraints in CVX

This is a non-convex constraint, except in one dimension.

However, you can constrain a matrix A to be negative semi-definite by constraining its negative to be (positive) semidefinite, or equivalently , by constraining lambda_max(A) <= 0 .

Many thanks!Thank you very much!

‘you can constrain a matrix A to be negative semi-definite by constraining its negative to be (positive) semidefinite’.Did you mean that I can denote the constraint as -A==semidefinite(N)?

Yes, as per your other question.

Ok! Got it! Thank you very much!