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From: "mwelinder at gmail dot com" <sourceware-bugzilla@sourceware.org>
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Subject: [Bug math/28472] pow(10, i) accuracy
Date: Mon, 24 Jan 2022 21:45:47 +0000
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https://sourceware.org/bugzilla/show_bug.cgi?id=3D28472

--- 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

--=20
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