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-rw-r--r--Docs/manual.texi65
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