nobu	2010-05-12 15:04:59 +0900 (Wed, 12 May 2010)

  New Revision: 27747

  http://svn.ruby-lang.org/cgi-bin/viewvc.cgi?view=rev&revision=27747

  Log:
    * ext/bigdecimal/lib/bigdecimal/math.rb (BigMath#log): improved
      precision and performance. [ruby-dev:41295]

  Modified files:
    branches/ruby_1_9_2/ChangeLog
    branches/ruby_1_9_2/ext/bigdecimal/lib/bigdecimal/math.rb
    branches/ruby_1_9_2/version.h
    trunk/ChangeLog
    trunk/ext/bigdecimal/lib/bigdecimal/math.rb

Index: ChangeLog
===================================================================
--- ChangeLog	(revision 27746)
+++ ChangeLog	(revision 27747)
@@ -1,3 +1,8 @@
+Wed May 12 15:04:57 2010  Nobuyoshi Nakada  <nobu@r...>
+
+	* ext/bigdecimal/lib/bigdecimal/math.rb (BigMath#log): improved
+	  precision and performance. [ruby-dev:41295]
+
 Wed May 12 11:39:10 2010  NAKAMURA Usaku  <usa@r...>
 
 	* ext/socket/extconf.rb: test all IPPROTO_* constants for recent Win32
Index: ext/bigdecimal/lib/bigdecimal/math.rb
===================================================================
--- ext/bigdecimal/lib/bigdecimal/math.rb	(revision 27746)
+++ ext/bigdecimal/lib/bigdecimal/math.rb	(revision 27747)
@@ -190,8 +190,10 @@
     one = BigDecimal("1")
     two = BigDecimal("2")
     n  = prec + BigDecimal.double_fig
-    if (expo = x.exponent) < 0
+    if (expo = x.exponent) < 0 || expo >= 3
       x = x.mult(BigDecimal("1E#{-expo}"), n)
+    else
+      expo = nil
     end
     x  = (x - one).div(x + one,n)
     x2 = x.mult(x,n)
@@ -206,7 +208,7 @@
       y += d
     end
     y *= two
-    if expo < 0
+    if expo
       y += log(BigDecimal("10"),prec) * BigDecimal(expo.to_s)
     end
     y
Index: ruby_1_9_2/ChangeLog
===================================================================
--- ruby_1_9_2/ChangeLog	(revision 27746)
+++ ruby_1_9_2/ChangeLog	(revision 27747)
@@ -1,3 +1,8 @@
+Wed May 12 15:04:57 2010  Nobuyoshi Nakada  <nobu@r...>
+
+	* ext/bigdecimal/lib/bigdecimal/math.rb (BigMath#log): improved
+	  precision and performance. [ruby-dev:41295]
+
 Tue May 11 14:26:00 2010  Kenta Murata <mrkn@m...>
 
 	* ext/bigdecimal/lib/bigdecimal/math.rb (atan),
Index: ruby_1_9_2/ext/bigdecimal/lib/bigdecimal/math.rb
===================================================================
--- ruby_1_9_2/ext/bigdecimal/lib/bigdecimal/math.rb	(revision 27746)
+++ ruby_1_9_2/ext/bigdecimal/lib/bigdecimal/math.rb	(revision 27747)
@@ -190,8 +190,10 @@
     one = BigDecimal("1")
     two = BigDecimal("2")
     n  = prec + BigDecimal.double_fig
-    if (expo = x.exponent) < 0
+    if (expo = x.exponent) < 0 || expo >= 3
       x = x.mult(BigDecimal("1E#{-expo}"), n)
+    else
+      expo = nil
     end
     x  = (x - one).div(x + one,n)
     x2 = x.mult(x,n)
@@ -206,7 +208,7 @@
       y += d
     end
     y *= two
-    if expo < 0
+    if expo
       y += log(BigDecimal("10"),prec) * BigDecimal(expo.to_s)
     end
     y
Index: ruby_1_9_2/version.h
===================================================================
--- ruby_1_9_2/version.h	(revision 27746)
+++ ruby_1_9_2/version.h	(revision 27747)
@@ -1,5 +1,5 @@
 #define RUBY_VERSION "1.9.2"
-#define RUBY_RELEASE_DATE "2010-05-11"
+#define RUBY_RELEASE_DATE "2010-05-12"
 #define RUBY_PATCHLEVEL -1
 
 #define RUBY_VERSION_MAJOR 1
@@ -7,7 +7,7 @@
 #define RUBY_VERSION_TEENY 1
 #define RUBY_RELEASE_YEAR 2010
 #define RUBY_RELEASE_MONTH 5
-#define RUBY_RELEASE_DAY 11
+#define RUBY_RELEASE_DAY 12
 
 #include "ruby/version.h"
 

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