[#28015] RCR: RUBY_VERSION_INT — Roger Pack <rogerdpack2@...>

Situation:

14 messages 2010/02/02

[#28113] [Bug #2723] $: length affects re-require time of already loaded files — Greg Hazel <redmine@...>

Bug #2723: $: length affects re-require time of already loaded files

16 messages 2010/02/08

[#28151] [Bug #2739] ruby 1.8.7 built with pthreads hangs under some circumstances — Joel Ebel <redmine@...>

Bug #2739: ruby 1.8.7 built with pthreads hangs under some circumstances

31 messages 2010/02/11

[#28188] [Bug #2750] build fails on win32/MinGW: "executable host ruby is required." even when --with-baseruby is used — Christian Bodt <redmine@...>

Bug #2750: build fails on win32/MinGW: "executable host ruby is required." even when --with-baseruby is used

9 messages 2010/02/16

[#28206] Is Math module a wrapper of libm? — Yusuke ENDOH <mame@...>

Hi matz --

23 messages 2010/02/18
[#28212] Re: Is Math module a wrapper of libm? — Yukihiro Matsumoto <matz@...> 2010/02/18

Hi,

[#28219] Re: Is Math module a wrapper of libm? — Yusuke ENDOH <mame@...> 2010/02/18

Hi,

[#28225] Re: Is Math module a wrapper of libm? — Marc-Andre Lafortune <ruby-core-mailing-list@...> 2010/02/18

Hi,

[#28233] Re: Is Math module a wrapper of libm? — Kenta Murata <muraken@...> 2010/02/18

Hi,

[#28265] Re: Is Math module a wrapper of libm? — Marc-Andre Lafortune <ruby-core-mailing-list@...> 2010/02/20

Hi,

[#28286] Re: Is Math module a wrapper of libm? — Kenta Murata <muraken@...> 2010/02/21

Hi

[#28291] Re: Is Math module a wrapper of libm? — Marc-Andre Lafortune <ruby-core-mailing-list@...> 2010/02/22

Hi!

[#28235] [Feature #2759] Regexp /g and /G options — Michael Fellinger <redmine@...>

Feature #2759: Regexp /g and /G options

35 messages 2010/02/18

[#28329] [ANN] Ruby 1.9.2dev has passed RubySpec! — Yusuke ENDOH <mame@...>

Hi,

12 messages 2010/02/24

[#28355] [ANN] Toward rich diversity of Ruby development. — Urabe Shyouhei <shyouhei@...>

A short announcement: thanks to some helps of GitHub people, I now have

12 messages 2010/02/27

[#28365] Indentifying key MRI-on-Windows issues — Jon <jon.forums@...>

In an effort to begin summarizing key MRI-on-Windows open issues I'm starting this thread in hopes that those interested will respond with details on the key MRI issues they feel need resolution for Windows users.

11 messages 2010/02/27
[#28690] Re: Indentifying key MRI-on-Windows issues — Roger Pack <rogerdpack2@...> 2010/03/16

> My key concern is http://blade.nagaokaut.ac.jp/cgi-bin/scat.rb/ruby/ruby-=

[ruby-core:28225] Re: Is Math module a wrapper of libm?

From: Marc-Andre Lafortune <ruby-core-mailing-list@...>
Date: 2010-02-18 15:25:38 UTC
List: ruby-core #28225
Hi,

> 2010/2/18 Yukihiro Matsumoto <matz@ruby-lang.org>:
> I choose #2.

Great!

On Thu, Feb 18, 2010 at 7:25 AM, Yusuke ENDOH <mame@tsg.ne.jp> wrote:
> At first, I'll soon change the behaviors of atanh(1) and lgamma(inf)
> which are currently platform-dependent. =A0According to SUSv3, the former
> should raise ERANGE (currently raises EDOM on Linux), and the latter
> should return inf (currently raises EDOM on darwin).

I disagree with this reading. SUSv3 states that atanh(1) should return
Infinity and (only when the application has requested that behavior)
set the ERANGE error flag. Ruby must choose to do one or the other (or
else add a way to do both). Mathematically speaking, there is no doubt
that it should return Infinity and that this is more helpful than
raising an error.

The question is also valid for
Math.log(0.0)
Math.atanh(1.0)
Math.gamma(0.0)
0.0**(-n)

Look at the graph of 1/x. Look at the graph of Log(x). Now explain to
me why 1/0.0 is +Inf and Log(x) would not be -Inf?

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