On the Cauchy index of a real rational function and the index theory of pseudo-lossless rational functions

  • Yves V. Genin
Conference paper
Part of the ISNM International Series of Numerical Mathematics book series (ISNM, volume 121)


The index theory relative to rational pseudo-lossless functions has been shown to be an interesting substitute for the Cauchy index theory and the argument principle theorem to discuss polynomial zero location problems. The reasons underlying this fact are put into light by working out the algebraic relations between these two equivalent approaches. A new simple proof of Kharitonov’s theorem is proposed to further illustrate this issue.


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Copyright information

© Birkhäuser Verlag Basel 1996

Authors and Affiliations

  • Yves V. Genin
    • 1
  1. 1.CESAMEUniversité Catholique de Louvain, Bâtiment EulerLouvain-La-NeuveBelgium

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