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Author mark.dickinson
Recipients gregory.p.smith, lukasz.langa, mark.dickinson, miss-islington, seberg, tim.peters, twouters
Date 2021-08-04.19:19:17
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Message-id <1628104757.73.0.206420953673.issue44698@roundup.psfhosted.org>
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> brave or foolhardy enough to try to figure out what all of the special case results *should* be for complex pow

Addendum: even the C standards give up at this point. For everything else the special cases are spelled out in detail, but for cpow, from §G.6.4.1 of C17 (in Annex G), we have:

> The cpow functions raise floating-point exceptions if appropriate for the calculation of the parts of the result, and may also raise spurious floating-point exceptions.

And that's it. (Well, not quite: there's a footnote, which says:

> This allows cpow(z, c) to be implemented as cexp(cclog(z)) without precluding implementations that treat special cases more carefully.

)
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Date User Action Args
2021-08-04 19:19:17mark.dickinsonsetrecipients: + mark.dickinson, tim.peters, twouters, gregory.p.smith, lukasz.langa, seberg, miss-islington
2021-08-04 19:19:17mark.dickinsonsetmessageid: <1628104757.73.0.206420953673.issue44698@roundup.psfhosted.org>
2021-08-04 19:19:17mark.dickinsonlinkissue44698 messages
2021-08-04 19:19:17mark.dickinsoncreate