An elementary proof of Mirsky's low rank approximation theorem

Chi-Kwong Li, Gilbert Strang
2020 The Electronic Journal of Linear Algebra  
An elementary proof is given for Mirsky's result on best low rank approximations of a given matrix with respect to all unitarily invariant norms.
doi:10.13001/ela.2020.5551 fatcat:ww3vevlhkvhevkigary7w6yr44