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hm, why not Chebfun? Result is a rational polynomial so we have to divide, but that seems fine/fast on servers.

Sollya can also do rational approximants, which are only faster in some circumstances, and Chebfun does not (as far as I know) account for floating point quantization, which is a big deal if you are trying to be accurate.

Possible misunderstanding: I mean a rational function in the sense of Padé approximation or CF [1], not just representing individual numbers as p/q. I did not find anything related to this in Sollya [2].

[1]: https://www.jstor.org/stable/2157229 [2]: https://www.sollya.org/releases/sollya-8.0/sollya-8.0.pdf

https://hal.science/hal-04093020/document

May not have been merged yet.

Pade approximants are also less useful than you might think - it's very hard to get to truly correctly rounded functions with the division.

Thanks! Yes, that (rminimax/ratapprox) looks very interesting. I got the impression that this was separate from Sollya.

Fair point about the correct rounding. We'd be fine with several ULPs.

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