On the perturbation bound in unitarily invariant norms for subunitary polar factors Original Research Article

Let image be the set of m×n complex matrices with rank r, and let image and image have the generalized polar decompositionsimageIn this article, a new perturbation bound for subunitary polar factors in any unitarily invariant norm is given byimagewhere image are the smallest positive singular values of A and image, respectively, which improves some existing perturbation bounds.