Function self_adjoint_evd 

pub fn self_adjoint_evd<T: ComplexField>(
    A: MatRef<'_, T>,
    s: DiagMut<'_, T>,
    u: Option<MatMut<'_, T>>,
    par: Par,
    stack: &mut MemStack,
    params: Spec<SelfAdjointEvdParams, T>,
) -> Result<(), EvdError>

computes the matrix $A$’s eigendecomposition, assuming it is self-adjoint

the eigenvalues are stored in $S$, and the eigenvectors in $U$ such that the eigenvalues are sorted in nondecreasing order

only the lower triangular half of $A$ is accessed