* math.c (math_log): update document to mention second optional

  argument for logarithm base.

git-svn-id: http://svn.ruby-lang.org/repos/ruby/trunk@11761 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 3 insertions, 0 deletions

diff --git a/math.c b/math.c
index 2675c71e6..bd0284900 100644
--- a/math.c
+++ b/math.c
@@ -305,8 +305,11 @@ math_exp(VALUE obj, VALUE x)
 /*
  *  call-seq:
  *     Math.log(numeric)    => float
+ *     Math.log(num,base)   => float
  *  
  *  Returns the natural logarithm of <i>numeric</i>.
+ *  If additional second argument is given, it will be the base
+ *  of logarithm.
  */
 
 static VALUE