This work is based in part on code from NetBSD libm, libc and kernel. The library is partly public domain and partly BSD-style licensed.
128 lines
3.2 KiB
Groff
128 lines
3.2 KiB
Groff
.\" Copyright (c) 1985, 1991 Regents of the University of California.
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.\" All rights reserved.
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.\"
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.\" Redistribution and use in source and binary forms, with or without
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.\" modification, are permitted provided that the following conditions
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.\" are met:
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.\" 1. Redistributions of source code must retain the above copyright
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.\" notice, this list of conditions and the following disclaimer.
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.\" 2. Redistributions in binary form must reproduce the above copyright
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.\" notice, this list of conditions and the following disclaimer in the
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.\" documentation and/or other materials provided with the distribution.
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.\" 3. Neither the name of the University nor the names of its contributors
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.\" may be used to endorse or promote products derived from this software
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.\" without specific prior written permission.
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.\"
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.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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.\" SUCH DAMAGE.
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.\"
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.\" from: @(#)exp.3 6.12 (Berkeley) 7/31/91
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.\" $FreeBSD: src/lib/msun/man/exp.3,v 1.24 2008/01/18 21:43:00 das Exp $
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.\" $NetBSD: exp.3,v 1.28 2011/09/17 10:52:52 jruoho Exp $
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.\"
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.Dd September 13, 2011
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.Dt EXP 3
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.Os
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.Sh NAME
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.Nm exp ,
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.Nm expf ,
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.\" The sorting error is intentional. exp and expf should be adjacent.
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.Nm exp2 ,
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.Nm exp2f ,
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.\" .Nm exp2l ,
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.Nm expm1 ,
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.Nm expm1f ,
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.Nd exponential functions
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.Sh LIBRARY
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.Lb libm
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.Sh SYNOPSIS
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.In math.h
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.Ft double
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.Fn exp "double x"
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.Ft float
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.Fn expf "float x"
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.Ft double
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.Fn exp2 "double x"
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.Ft float
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.Fn exp2f "float x"
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.\" .Ft long double
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.\" .Fn exp2l "long double x"
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.Ft double
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.Fn expm1 "double x"
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.Ft float
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.Fn expm1f "float x"
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.Sh DESCRIPTION
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The
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.Fn exp
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and the
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.Fn expf
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functions compute the base
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.Ms e
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exponential value of the given argument
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.Fa x .
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.Pp
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The
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.Fn exp2 ,
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and
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.Fn exp2f
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.\" .Fn exp2f ,
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.\" and
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.\" .Fn exp2l
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functions compute the base 2 exponential of the given argument
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.Fa x .
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.Pp
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The
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.Fn expm1
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and the
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.Fn expm1f
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functions computes the value exp(x)\-1 accurately even for tiny argument
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.Fa x .
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.Sh RETURN VALUES
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These functions will return the appropriate computation unless an error
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occurs or an argument is out of range.
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The functions
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.Fn exp
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and
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.Fn expm1
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detect if the computed value will overflow,
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set the global variable
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.Va errno
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to
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.Er ERANGE
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and cause a reserved operand fault on a
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.Tn VAX .
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.Sh SEE ALSO
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.Xr math 3
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.Sh STANDARDS
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The
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.Fn exp
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functions conform to
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.St -ansiC .
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The
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.Fn exp2 ,
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.Fn exp2f ,
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.Fn expf ,
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.Fn expm1 ,
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and
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.Fn expm1f
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functions conform to
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.St -isoC-99 .
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.Sh HISTORY
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The
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.Fn exp
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functions appeared in
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.At v6 .
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The
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.Fn expm1
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function appeared in
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.Bx 4.3 .
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