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arXiv · 0705.4369

Computing Integer Powers in Floating-Point Arithmetic

Peter Kornerup·Vincent Lefèvre·Jean-Michel Muller
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Abstract

We introduce two algorithms for accurately evaluating powers to a positive integer in floating-point arithmetic, assuming a fused multiply-add (fma) instruction is available. We show that our log-time algorithm always produce faithfully-rounded results, discuss the possibility of getting correctly rounded results, and show that results correctly rounded in double precision can be obtained if extended-precision is available with the possibility to round into double precision (with a single rounding).

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Peter Kornerup, Vincent Lefèvre, Jean-Michel Muller. 2007-05-30. Computing Integer Powers in Floating-Point Arithmetic. https://arxiv.org/abs/0705.4369

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