From: foldes.laszlo2@gmail.com
To: ruby-core@ruby-lang.org
Subject: [ruby-core:100297] [Ruby master Bug#17214] BigDecimal exponentiation gives incorrect results
Date: Mon, 05 Oct 2020 00:35:36 +0000 (UTC) [thread overview]
Message-ID: <redmine.issue-17214.20201005003535.5802@ruby-lang.org> (raw)
In-Reply-To: redmine.issue-17214.20201005003535.5802@ruby-lang.org
Issue #17214 has been reported by karatedog (Földes László).
----------------------------------------
Bug #17214: BigDecimal exponentiation gives incorrect results
https://bugs.ruby-lang.org/issues/17214
* Author: karatedog (Földes László)
* Status: Open
* Priority: Normal
* ruby -v: ruby 2.7.1p83 (2020-03-31 revision a0c7c23c9c) [x86_64-linux]
* Backport: 2.5: UNKNOWN, 2.6: UNKNOWN, 2.7: UNKNOWN
----------------------------------------
> (BigDecimal("2222") ** BigDecimal("3.5")).to_i
=> 517135311000
This is an incorrect value.
> 2222 ** 3.5
=> 517135308457.25256
This is the correct value (within Float precision).
As the Base gets larger, the problem is more visible:
> (BigDecimal("22222") ** BigDecimal("3.5")).to_i
=> 1635840670000000
Wrong value, number of trailing zeroes increase.
> 22222 ** 3.5
=> 1635840670214066.5 (nearing maximum Float precision)
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next parent reply other threads:[~2020-10-05 0:35 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-10-05 0:35 foldes.laszlo2 [this message]
2020-10-05 5:08 ` [ruby-core:100298] [Ruby master Bug#17214] BigDecimal exponentiation gives incorrect results nobu
2020-10-05 11:16 ` [ruby-core:100299] " foldes.laszlo2
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