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From: "mwelinder at gmail dot com" <sourceware-bugzilla@sourceware.org>
To: glibc-bugs@sourceware.org
Subject: [Bug math/28472] pow(10, i) accuracy
Date: Mon, 24 Jan 2022 21:45:47 +0000 [thread overview]
Message-ID: <bug-28472-131-Tpasc0djnu@http.sourceware.org/bugzilla/> (raw)
In-Reply-To: <bug-28472-131@http.sourceware.org/bugzilla/>
https://sourceware.org/bugzilla/show_bug.cgi?id=28472
--- Comment #6 from M Welinder <mwelinder at gmail dot com> ---
> I'd encourage using exp10
At present that seems to be a very bad idea. The accuracy is worse than
pow(10,i).
For example, here are the integer powers of 10 from 0-21. Problems with 6/22
results.
1.00000000000000000000000000000000000
10.00000000000000000000000000000000000
100.00000000000000000000000000000000000
1000.00000000000011368683772161602973938
10000.00000000000181898940354585647583008
100000.00000000000000000000000000000000000
1000000.00000000000000000000000000000000000
9999999.99999999813735485076904296875000000
99999999.99999998509883880615234375000000000
999999999.99999988079071044921875000000000000
10000000000.00000000000000000000000000000000000
100000000000.00000000000000000000000000000000000
1000000000000.00000000000000000000000000000000000
10000000000000.00000000000000000000000000000000000
100000000000000.00000000000000000000000000000000000
1000000000000000.00000000000000000000000000000000000
10000000000000000.00000000000000000000000000000000000
99999999999999984.00000000000000000000000000000000000
1000000000000000000.00000000000000000000000000000000000
10000000000000000000.00000000000000000000000000000000000
100000000000000000000.00000000000000000000000000000000000
1000000000000000000000.00000000000000000000000000000000000
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next prev parent reply other threads:[~2022-01-24 21:45 UTC|newest]
Thread overview: 26+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-10-18 23:54 [Bug math/28472] New: " mwelinder at gmail dot com
2021-10-19 15:44 ` [Bug math/28472] " joseph at codesourcery dot com
2021-10-19 21:28 ` mwelinder at gmail dot com
2021-10-19 21:42 ` joseph at codesourcery dot com
2021-10-25 8:44 ` newbie-02 at gmx dot de
2021-11-14 5:38 ` newbie-02 at gmx dot de
2022-01-24 21:45 ` mwelinder at gmail dot com [this message]
2022-01-24 21:56 ` joseph at codesourcery dot com
2022-09-23 16:33 ` newbie-02 at gmx dot de
2023-01-09 14:43 ` newbie-02 at gmx dot de
2023-01-09 18:35 ` joseph at codesourcery dot com
2023-01-09 21:23 ` newbie-02 at gmx dot de
2023-01-09 21:36 ` joseph at codesourcery dot com
2023-01-10 0:23 ` newbie-02 at gmx dot de
2024-03-02 22:53 ` vincent-srcware at vinc17 dot net
2024-03-04 14:58 ` wdijkstr at arm dot com
2024-03-04 15:35 ` vincent-srcware at vinc17 dot net
2024-03-04 16:07 ` wdijkstr at arm dot com
2024-03-04 17:09 ` vincent-srcware at vinc17 dot net
2024-03-04 18:27 ` wdijkstr at arm dot com
2024-03-04 19:23 ` vincent-srcware at vinc17 dot net
2024-03-18 21:09 ` newbie-02 at gmx dot de
2024-03-18 22:17 ` wdijkstr at arm dot com
2024-03-20 9:02 ` newbie-02 at gmx dot de
2024-03-20 9:56 ` vincent-srcware at vinc17 dot net
2024-03-20 13:54 ` wdijkstr at arm dot com
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