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arXiv · 1511.00774

A new application methodology of the Fourier transform for rational approximation of the complex error function

Abstract

This paper presents a new approach in application of the Fourier transform to the complex error function resulting in an efficient rational approximation. Specifically, the computational test shows that with only $17$ summation terms the obtained rational approximation of the complex error function provides the average accuracy ${10^{ - 15}}$ over the most domain of practical importance $0 \le x \le 40,000$ and ${10^{ - 4}} \le y \le {10^2}$ required for the HITRAN-based spectroscopic applications. Since the rational approximation does not contain trigonometric or exponential functions dependent upon the input parameters $x$ and $y$, it is rapid in computation. Such an example demonstrates that the considered methodology of the Fourier transform may be advantageous in practical applications.

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BibTeXRIS

S. M. Abrarov, B. M. Quine. 2016-01-31. A new application methodology of the Fourier transform for rational approximation of the complex error function. https://doi.org/10.5539/jmr.v8n1p14

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