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Re: Inaccurate results from numeric ln(), log(), exp() and pow() - Mailing list pgsql-hackers

From Dean Rasheed
Subject Re: Inaccurate results from numeric ln(), log(), exp() and pow()
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Msg-id CAEZATCU4mKZD+BC2gBWySXB-mr4AUMzccVV3j6CXTc_15p_tWw@mail.gmail.com
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In response to Re: Inaccurate results from numeric ln(), log(), exp() and pow()  (Dean Rasheed <dean.a.rasheed@gmail.com>)
Responses Re: Inaccurate results from numeric ln(), log(), exp() and pow()  (Tom Lane <tgl@sss.pgh.pa.us>)
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On 14 November 2015 at 00:16, Dean Rasheed <dean.a.rasheed@gmail.com> wrote:
> I can't see a way to make that work reliably. It would need to be
> 10^estimate_ln_weight(base) and the problem is that both exp and
> ln_weight could be too big to fit in double variables, and become
> HUGE_VAL, losing all precision.

Of course I meant 10^ln_weight could be too big to fit in a double.

Regards,
Dean

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