Expressing $ \sum_{\lambda\in\text{Spec}(\mathbf{X})} \lambda \log \lambda$

44 Views Asked by At

Say $\text{Spec}(\mathbf{X})$ is a set of eigenvalues of a real positive definite matrix $\mathbf{X}$.

How do I express $$ \sum_{\lambda\in\text{Spec}(\mathbf{X})} \lambda \log \lambda$$ without explicitly finding the eigenvalues?