Skip to main content
Log in

Rational Unimodular Interpolation on the Unit Circle

  • Published:
Computational Methods and Function Theory Aims and scope Submit manuscript

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.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Similar content being viewed by others

References

  1. D. G. Cantor and R. R. Phelps, An elementary interpolation theorem, Proc. Amer. Math. Soc. 16 (1965), 523–525.

    Article  MathSciNet  MATH  Google Scholar 

  2. C. Glader and G. Högnäs, An equioscillation characterization of finite Blaschke products, Complex Variables 42 2000) No.2, 107–118.

    Article  MathSciNet  MATH  Google Scholar 

  3. C. Glader and M. Lindström, Finite Blaschke product interpolation on the closed unit disc, J. Math. Anal. Appl. 273 2002) No.2, 417–427.

    Article  MathSciNet  MATH  Google Scholar 

  4. W. B. Jones and S. Ruscheweyh, Blaschke product interpolation and its application to the design of digital filters, Constr. Approx. 3 1987) No.4, 405–409.

    Article  MathSciNet  MATH  Google Scholar 

  5. G. Semmler and E. Wegert, Nonlinear Riemann-Hilbert problems and boundary interpolation, Comput. Methods Funct. Theory 3 2003) No.1, 179–199.

    MathSciNet  MATH  Google Scholar 

  6. G. Semmler and E. Wegert, Boundary interpolation with Blaschke products of minimal degree, Comput. Methods Funct. Theory 6 2006) No.2, 493–511.

    MathSciNet  MATH  Google Scholar 

  7. R. Younis, Interpolation by a finite Blaschke product, Proc. Amer. Math. Soc. 78 1980) No.3, 451–452.

    MathSciNet  MATH  Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Christer Glader.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Glader, C. Rational Unimodular Interpolation on the Unit Circle. Comput. Methods Funct. Theory 6, 481–492 (2006). https://doi.org/10.1007/BF03321625

Download citation

  • Received:

  • Revised:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/BF03321625

Keywords

2000 MSC

Navigation