https://fr.mathworks.com/help/matlab/ref/ordschur.html
ordschur - Reorder eigenvalues in Schur factorization - MATLAB
This MATLAB function reorders the Schur factorization X = U*T*U' produced by [U,T] = schur(X) and returns the reordered Schur matrix TS and the orthogonal...
reordereigenvaluesschurfactorizationmatlab