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  4. Chebyshev approximation by the exponent from a rational expression

Chebyshev approximation by the exponent from a rational expression

MMC.
2025;
Volume 12, Number 1
: pp. 233–240
Received: March 05, 2024
Revised: November 05, 2024
Accepted: February 22, 2025

Malachivskyi R. P., Bun R. A., Medynskyi I. P.  Chebyshev approximation by the exponent from a rational expression.  Mathematical Modeling and Computing. Vol. 12, No. 1, pp. 233–240 (2025)   

Authors:
  1. R. P. Malachivskyi
  2. R. A. Bun
  3. I. P. Medynskyi
1
Lviv Polytechnic National University
2
Lviv Polytechnic National University; WSB University
3
Lviv Polytechnic National University

A method for constructing Chebyshev approximation with relative error of the exponential from a rational expression is proposed.  It implies constructing an intermediate Chebyshev approximation with absolute error by a rational expression of the logarithm of the function being approximated.  The approximation by a rational expression is calculated as the boundary mean-power approximation using an iterative scheme based on the least squares method with two variable weight functions.  The presented results of solving test examples confirm the fast convergence of the method.

Chebyshev approximation by exponential expression
Rational Expression
mean-power approximation
least squares method
variable weight function
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