Computed multivalues of AGM reveal periodicities of inverse functions

  • Francois Lamarche TeledyneLeCroy, 700 Chestnut Ridge rd., Chestnut Ridge, NY10977 USA
  • Helmut Ruhland Independent Researcher
Keywords: arithmetic, geometric, mean

Abstract

The article shows how two choices are possible whenever computing the geometric mean, and the repetition of this process can in general yield 2-to-the power N different values
when the choices are compounded in the first N steps of evaluation of the arithmeticgeometric mean. This happens not only in the simple AGM involved in the computation of the complete elliptic integral of the first kind, but also in analogous methods for the computation of the complete and incomplete elliptic integrals of the first and second kind.

Author Biographies

Francois Lamarche, TeledyneLeCroy, 700 Chestnut Ridge rd., Chestnut Ridge, NY10977 USA

Dr., PhD, TeledyneLeCroy, USA, francois.lamarche@teledyne.com

Helmut Ruhland, Independent Researcher

MSc, Independent Researcher, Santa Fe, La Habana, Cuba, helmut.ruhland50@web.de

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Published
2022-11-24
How to Cite
Lamarche, F., & Ruhland, H. (2022). Computed multivalues of AGM reveal periodicities of inverse functions. Computer Tools in Education, (3), 64-81. https://doi.org/10.32603/2071-2340-2022-3-64-81
Section
Algorithmic mathematics and mathematical modelling