Introduce a new log(3) manpage and move the relevant functions there.

Document exp2l() in exp(3), and remove the quaint discussion of topics
such as what these functions were called on the HP-71B's variant of
BASIC.

2 files changed, 118 insertions, 69 deletions

diff --git a/lib/msun/man/exp.3 b/lib/msun/man/exp.3
index b470f1c..b051e5b 100644
--- a/lib/msun/man/exp.3
+++ b/lib/msun/man/exp.3
@@ -28,7 +28,7 @@
 .\"     from: @(#)exp.3	6.12 (Berkeley) 7/31/91
 .\" $FreeBSD$
 .\"
-.Dd April 5, 2005
+.Dd January 17, 2008
 .Dt EXP 3
 .Os
 .Sh NAME
@@ -37,17 +37,12 @@
 .\" The sorting error is intentional.  exp and expf should be adjacent.
 .Nm exp2 ,
 .Nm exp2f ,
+.Nm exp2l ,
 .Nm expm1 ,
 .Nm expm1f ,
-.Nm log ,
-.Nm logf ,
-.Nm log10 ,
-.Nm log10f ,
-.Nm log1p ,
-.Nm log1pf ,
 .Nm pow ,
 .Nm powf
-.Nd exponential, logarithm, power functions
+.Nd exponential and power functions
 .Sh LIBRARY
 .Lb libm
 .Sh SYNOPSIS
@@ -60,23 +55,13 @@
 .Fn exp2 "double x"
 .Ft float
 .Fn exp2f "float x"
+.Ft long double
+.Fn exp2l "long double x"
 .Ft double
 .Fn expm1 "double x"
 .Ft float
 .Fn expm1f "float x"
 .Ft double
-.Fn log "double x"
-.Ft float
-.Fn logf "float x"
-.Ft double
-.Fn log10 "double x"
-.Ft float
-.Fn log10f "float x"
-.Ft double
-.Fn log1p "double x"
-.Ft float
-.Fn log1pf "float x"
-.Ft double
 .Fn pow "double x" "double y"
 .Ft float
 .Fn powf "float x" "float y"
@@ -91,9 +76,10 @@ exponential value of the given argument
 .Fa x .
 .Pp
 The
-.Fn exp2
-and the
-.Fn exp2f
+.Fn exp2 ,
+.Fn exp2f ,
+and
+.Fn exp2l
 functions compute the base 2 exponential of the given argument
 .Fa x .
 .Pp
@@ -105,29 +91,6 @@ functions compute the value exp(x)\-1 accurately even for tiny argument
 .Fa x .
 .Pp
 The
-.Fn log
-and the
-.Fn logf
-functions compute the value of the natural logarithm of argument
-.Fa x .
-.Pp
-The
-.Fn log10
-and the
-.Fn log10f
-functions compute the value of the logarithm of argument
-.Fa x
-to base 10.
-.Pp
-The
-.Fn log1p
-and the
-.Fn log1pf
-functions compute
-the value of log(1+x) accurately even for tiny argument
-.Fa x .
-.Pp
-The
 .Fn pow
 and the
 .Fn powf
@@ -159,30 +122,7 @@ raise an invalid exception and return an \*(Na if
 < 0 and
 .Fa y
 is not an integer.
-An attempt to take the logarithm of \*(Pm0 will result in
-a divide-by-zero exception, and an infinity will be returned.
-An attempt to take the logarithm of a negative number will
-result in an invalid exception, and an \*(Na will be generated.
 .Sh NOTES
-The functions exp(x)\-1 and log(1+x) are called
-expm1 and logp1 in
-.Tn BASIC
-on the Hewlett\-Packard
-.Tn HP Ns \-71B
-and
-.Tn APPLE
-Macintosh,
-.Tn EXP1
-and
-.Tn LN1
-in Pascal, exp1 and log1 in C
-on
-.Tn APPLE
-Macintoshes, where they have been provided to make
-sure financial calculations of ((1+x)**n\-1)/x, namely
-expm1(n\(**log1p(x))/x, will be accurate when x is tiny.
-They also provide accurate inverse hyperbolic functions.
-.Pp
 The function
 .Fn pow x 0
 returns x**0 = 1 for all x including x = 0, \*(If, and \*(Na .
@@ -229,4 +169,9 @@ and infinite x, i.e., independently of x.
 .El
 .Sh SEE ALSO
 .Xr fenv 3 ,
+.Xr ldexp 3 ,
+.Xr log 3 ,
 .Xr math 3
+.Sh STANDARDS
+These functions conform to
+.St -isoC-99 .
diff --git a/lib/msun/man/log.3 b/lib/msun/man/log.3
new file mode 100644
index 0000000..1934473
--- /dev/null
+++ b/lib/msun/man/log.3
@@ -0,0 +1,104 @@
+.\" Copyright (c) 2008 David Schultz <das@FreeBSD.org>
+.\" All rights reserved.
+.\"
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following conditions
+.\" are met:
+.\" 1. Redistributions of source code must retain the above copyright
+.\"    notice, this list of conditions and the following disclaimer.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\"    notice, this list of conditions and the following disclaimer in the
+.\"    documentation and/or other materials provided with the distribution.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+.\" SUCH DAMAGE.
+.\"
+.\" $FreeBSD$
+.\"
+.Dd January 17, 2008
+.Dt LOG 3
+.Os
+.Sh NAME
+.Nm log ,
+.Nm logf ,
+.Nm logl ,
+.Nm log10 ,
+.Nm log10f ,
+.Nm log1p ,
+.Nm log1pf
+.Nd logarithm functions
+.Sh LIBRARY
+.Lb libm
+.Sh SYNOPSIS
+.In math.h
+.Ft double
+.Fn log "double x"
+.Ft float
+.Fn logf "float x"
+.Ft double
+.Fn log10 "double x"
+.Ft float
+.Fn log10f "float x"
+.Ft double
+.Fn log1p "double x"
+.Ft float
+.Fn log1pf "float x"
+.Sh DESCRIPTION
+The
+.Fn log
+and
+.Fn logf
+functions compute the natural logarithm of
+.Fa x .
+.Pp
+The
+.Fn log10
+and
+.Fn log10f
+functions compute the logarithm base 10 of
+.Fa x .
+.Pp
+The
+.Fn log1p
+and
+.Fn log1pf
+functions compute the natural logarithm of
+.No "1 + x" .
+Computing the natural logarithm as
+.Li log1p(x)
+is more accurate than computing it as
+.Li log(1 + x)
+when
+.Fa x
+is close to zero.
+.Sh RETURN VALUES
+These functions return the requested logarithm; the logarithm of 1 is +0.
+An attempt to take the logarithm of \*(Pm0 results in a divide-by-zero
+exception, and -\*(If is returned.
+Otherwise, attempting to take the logarithm of a negative number
+results in an invalid exception and a return value of \*(Na.
+.Sh SEE ALSO
+.Xr exp 3 ,
+.Xr ilogb 3 ,
+.Xr math 3 ,
+.Xr pow 3
+.Sh STANDARDS
+The
+.Fn log ,
+.Fn logf ,
+.Fn log10 ,
+.Fn log10f ,
+.Fn log1p ,
+and
+.Fn log1pf
+functions conform to
+.St -isoC-99 .