“…For the readers convenience, we mention here briefly some of these connections. One motivation comes from earlier work [1] on two-sided, and tangential, interpolation for matrix functions; see also references [2] through [5], and [14]. We make additional connections also to to interpolation in de Branges-Rovnyak spaces [13], to wavelet filters, see e.g., [17], and to iterated function systems, see [18] by Courtney, Muhly, and Schmidt, and [28] by Rochberg, to Hardy classes [29,30] and to classical harmonic analysis; see e.g., [32,33,34,35].…”