Abstract
We consider an interpolation problem with n pairwise distinct nodes z 1,…,z n and n numbers w 1,…,w n, all on the unit circle in the complex plane, and seek interpolants b(z) of minimal degree in the class consisting of ratios of finite Blaschke products. The focus is on cases where the interpolant of minimal degree is uniquely determined.
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Glader, C. Rational Unimodular Interpolation on the Unit Circle. Comput. Methods Funct. Theory 6, 481–492 (2006). https://doi.org/10.1007/BF03321625
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DOI: https://doi.org/10.1007/BF03321625