Chebyshev approximation of the steel magnetization characteristic by the sum of a linear expression and an arctangent function

2019;
: pp. 77-84
https://doi.org/10.23939/mmc2019.01.077
Received: March 06, 2019
Accepted: April 08, 2019
1
Centre of Mathematical Modelling of Ukrainian National Academy of Sciences; Ukrainian Akademy of Printing
2
Lviv Polytechnic National University

The properties of a Chebyshev approximation by the sum of a linear expression and an arctangent function have been investigated.  The condition has been established under which a Chebyshev approximation by this expression with the smallest absolute error and with the reproduction of the function value at the leftmost point exists and is unique.  A method of determining the parameters of this approximation has been suggested and substantiated.  The results of a Chebyshev approximation of the magnetization characteristic of electrotechnical steel by the sum of a linear expression and an arctangent function have been presented.

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Math. Model. Comput. Vol.6, No.1, pp.77-84 (2019)