Arjens LOG functions changes with small changes and tests added to mysql-test

Docs/manual.texi:
  Manual changes to doccument new functions and function changes
mysql-test/r/func_math.result:
  Extend tests for LOG family functions
mysql-test/t/func_math.test:
  Extend tests for LOG family functions
sql/gen_lex_hash.cc:
  Lex hash changes
sql/item_create.cc:
  Rename old log function to ln
sql/item_create.h:
  More log functions
sql/item_func.cc:
  Implementation of new log function behavior
sql/item_func.h:
  Class definition for new functions
sql/lex.h:
  Function names
sql/sql_yacc.yy:
  Symbols for new LOG function
tests/function.res:
  One more test result change
tests/function.tst:
  One more test change
BitKeeper/etc/logging_ok:
  Logging to logging@openlogging.org accepted

1 files changed, 60 insertions, 5 deletions

diff --git a/Docs/manual.texi b/Docs/manual.texi
index 83999b6daae..93272140507 100644
--- a/Docs/manual.texi
+++ b/Docs/manual.texi
@@ -31874,17 +31874,57 @@ mysql> SELECT EXP(2);
 mysql> SELECT EXP(-2);
         -> 0.135335
 @end example
-@findex LOG()
-@item LOG(X)
+
+@findex LN()
+@item LN(X)
 Returns the natural logarithm of @code{X}:
 @example
+mysql> SELECT LN(2);
+        -> 0.693147
+mysql> SELECT LN(-2);
+        -> NULL
+@end example
+
+This function was added in MySQL version 4.0.3.
+It is synonymous with @code{LOG(X)} in MySQL.
+
+@findex LOG()
+@item LOG([B,]X)
+When called with one parameter, this function returns the natural logarithm
+of @code{X}:
+@example
 mysql> SELECT LOG(2);
         -> 0.693147
 mysql> SELECT LOG(-2);
         -> NULL
 @end example
-If you want the log of a number @code{X} to some arbitary base @code{B}, use
-the formula @code{LOG(X)/LOG(B)}.
+
+When called with two parameters, this function returns the logarithm of
+@code{X} for an arbitary base @code{B}:
+@example
+mysql> SELECT LOG(2,65536);
+        -> 16.000000
+mysql> SELECT LOG(1,100);
+        -> NULL
+@end example
+
+The arbitrary base option was added in MySQL version 4.0.3.
+@code{LOG(B,X)} is equivalent to @code{LOG(X)/LOG(B)}.
+
+@findex LOG2()
+@item LOG2(X)
+Returns the base-2 logarithm of @code{X}:
+@example
+mysql> SELECT LOG2(65536);
+        -> 16.000000
+mysql> SELECT LOG2(-100);
+        -> NULL
+@end example
+
+@code{LOG2()} is useful for finding out how many bits a number would
+require for storage.
+This function was added in MySQL version 4.0.3.
+In earlier versions, you can use @code{LOG(X)/LOG(2)} instead.
 
 @findex LOG10()
 @item LOG10(X)
@@ -49674,12 +49714,27 @@ Our TODO section contains what we plan to have in 4.0. @xref{TODO MySQL 4.0}.
 @cindex changes, version 4.0
 
 @menu
+* News-4.0.3::                  Changes in release 4.0.3
 * News-4.0.2::                  Changes in release 4.0.2 (01 July 2002)
 * News-4.0.1::                  Changes in release 4.0.1 (23 Dec 2001)
 * News-4.0.0::                  Changes in release 4.0.0 (Oct 2001: Alpha)
 @end menu
 
-@node News-4.0.2, News-4.0.1, News-4.0.x, News-4.0.x
+@node News-4.0.3, News-4.0.2, News-4.0.x, News-4.0.x
+@appendixsubsec Changes in release 4.0.3
+
+@itemize @bullet
+@item
+Extended @code{LOG()} function to accept an optional arbitrary base parameter.
+@xref{Mathematical functions}.
+@item
+Added @code{LOG2()} function (useful for finding out how many bits a number would require for storage).
+@item
+Added @code{LN()} natural logarithm function for compatibility with other databases. It is synonymous with @code{LOG(X)}.
+@end itemize
+
+
+@node News-4.0.2, News-4.0.1, News-4.0.3, News-4.0.x
 @appendixsubsec Changes in release 4.0.2 (01 July 2002)
 
 @itemize @bullet