# \[Bug #3279\] BigMath::log is very slow

**URL:** <https://www.ruby-forum.com/t/bug-3279-bigmath-log-is-very-slow/188450>\
**Category:** Development\
**Created:** [May 12, 2010, 7:16am UTC](https://www.ruby-forum.com/t/bug-3279-bigmath-log-is-very-slow/188450 "2010-05-12T07:16:43Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![asarih](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/9de053/32.png) [@asarih](https://www.ruby-forum.com/u/asarih)\
**Post date:** [May 12, 2010, 7:16am UTC](https://www.ruby-forum.com/t/bug-3279-bigmath-log-is-very-slow/188450/1 "2010-05-12T07:16:43Z")

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Bug #3279: BigMath::log is very slow  
[http://redmine.ruby-lang.org/issues/show/3279](http://redmine.ruby-lang.org/issues/show/3279)

e$B5/I\<\<Te(B: Hiro A.  
e$B%9%F!\<%?%9e(B: Open, e$BM%@hEYe(B: Normal  
e$B%+%F%4%je(B: lib  
ruby -v: ruby 1.9.2dev (2010-04-19 trunk 27396) [x86\_64-darwin10.3.0]

[http://bugs.jruby.org/4787](http://bugs.jruby.org/4787)  
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log(BigDecimal(“1000”),100)e$B$@$H\>.?tE@0J2\<e(B110e$B7e$/$i$$!"e(Blog(BigDecimal(“0.0001”),200)e$B$@$He(B210e$B7e$/$i$$!#e(B

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<div class="post-metadata">

**Author:** ![asarih](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/9de053/32.png) [@asarih](https://www.ruby-forum.com/u/asarih)\
**Post date:** [May 12, 2010, 11:25am UTC](https://www.ruby-forum.com/t/bug-3279-bigmath-log-is-very-slow/188450/2 "2010-05-12T11:25:28Z")

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e$B$`$i$?$G$9!#e(B

On 2010/05/12, at 14:16, Hiro A. wrote:

> [http://bugs.jruby.org/4787](http://bugs.jruby.org/4787) e$B$G!“$3$N4X?t$OHs\>o$KCY$$$H8@$&Js9p$,$”$j$^$7$?!#e(B  
> JRubye$B$G$be(BRubiniuse$B$G$bCY$$$N$G@'Hs$H$be(BMRIe$B$NJ}$GBP=h$7$FM\_$7$$$G$9!#e(B
> 
> e$B\>e$N%A%1%C%H$G\<($5$l$F$$$k%Q%C%A$r;n$7$?$H$3$m!"MW5a$5$l$?@:EY$^$G$O@53N$JJ\*$rJV$9$h$&$G$9!#Nc$($Pe(B log(BigDecimal(“1000”),100)e$B$@$H\>.?tE@0J2\<e(B110e$B7e$/$i$$!"e(Blog(BigDecimal(“0.0001”),200)e$B$@$He(B210e$B7e$/$i$$!#e(B
> 
> e$B8!F$$7$F2\<$5$$!#$3$l$,2~A1$5$l$k$N$G$"$l$Pe(B1.8e$B$X$N%P%C%/%]!\<%H$b=E$M$F8!F$$7$F2\<$5$$!#e(B

e$B\>e5-%A%1%C%H$N%Q%C%A$Oe(B trunk e$B$K%^!\<%8$7$^$9!#e(B  
ruby\_1\_9\_2  
e$B%V%i%s%A$X$N%P%C%/%]!\<%H$bLdBj$J$$$H;W$$$^$9$N$GF1;~$K$d$j$^$9!#e(B

1.8 e$B$X$N%P%C%/%]!\<%H$K$D$$$F$O;d$OH=CG$G$-$^$;$s$N$G!“e(B  
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–  
Kenta M.  
OpenPGP FP = FA26 35D7 4F98 3498 0810 E0D5 F213 966F E9EB 0BCC

e$BK$r=q$-$^$7$?e(B!!  
e$B!Xe(BRuby e$B5U0z$-%l%7%T!Ye(B

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E-mail: removed\_email\_address@domain.invalid  
twitter: [http://twitter.com/mrkn/](http://twitter.com/mrkn/)  
blog: [ドレッシングのような](http://d.hatena.ne.jp/mrkn/)

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<div class="post-metadata">

**Author:** ![asarih](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/9de053/32.png) [@asarih](https://www.ruby-forum.com/u/asarih)\
**Post date:** [May 30, 2010, 9:49am UTC](https://www.ruby-forum.com/t/bug-3279-bigmath-log-is-very-slow/188450/3 "2010-05-30T09:49:18Z")

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e$B%A%1%C%He(B #3279 e$B$,99?7$5$l$^$7$?!#e(B (by Yusuke E.)

r27747 e$B$Ge(B trunk e$B$O=$@5:Q$\_$G$9$N$G!"e(B1.9.1 e$B$Ne(B backport  
e$B$K0$7$F$\*$-$^$9!#e(B

## – Yusuke E. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid)

[http://redmine.ruby-lang.org/issues/show/3279](http://redmine.ruby-lang.org/issues/show/3279)

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<div class="post-metadata">

**Author:** ![asarih](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/9de053/32.png) [@asarih](https://www.ruby-forum.com/u/asarih)\
**Post date:** [May 12, 2010, 10:15pm UTC](https://www.ruby-forum.com/t/bug-3279-bigmath-log-is-very-slow/188450/4 "2010-05-12T22:15:58Z")

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e$B%A%1%C%He(B #3279 e$B$,99?7$5$l$^$7$?!#e(B (by Hiro A.)

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Rubiniuse$B$G$O$^$@$^$@CY$$!Je(Bbigdecimal/math.rbe$B$r:9$7BX$($F;n$7$^$7$?!K$G$9$N$G!“$3$N%Q%C%A$r\<h$j9~$s$G$b$i$$$?$$!”$H$$$&J}8~$KJQ$o$j$O$“$j$^$;$s!#$”$H!"e(BEvane$B$He(BBriane$B$K$b$3$NE@$K$OCm0U$r4-5/$7$^$7$?$N$G!“2~A1$,;$5$l$k2DG=@-$O$”$j$^$9!#e(B

## e$B59$7$/$\*4j$$$7$^$9!#e(B

[http://redmine.ruby-lang.org/issues/show/3279](http://redmine.ruby-lang.org/issues/show/3279)