Abstract
Functions that calculate correctly rounded exponents provide the best approximation and ensure cross-platform portability. This paper presents an algorithm for calculating the correctly rounded value of the exponential function when its argument and value are double-precision numbers and the calculations use extended double-precision arithmetic. The formal description of the algorithm is provided. The proposed algorithm is implemented as a C function. The results of its testing, including the measurement of its time characteristics and comparison with other algorithms, are presented.
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This work was carried out in the framework of the state task “Investigation and implementation of a software platform for advanced multicore processors” (FNEF-2022-002).
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Translated by Yu. Kornienko
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Godunov, A.N. Algorithm for Calculating Correctly Rounded Exponential Function in Double Precision Using Double-Extended Arithmetic. Program Comput Soft 48, 369–375 (2022). https://doi.org/10.1134/S0361768822060032
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DOI: https://doi.org/10.1134/S0361768822060032