freebsd-dev/usr.bin/bc/bc.library
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/* $FreeBSD$ */
/* $OpenBSD: bc.library,v 1.4 2012/03/14 07:35:53 otto Exp $ */
/*
* Copyright (C) Caldera International Inc. 2001-2002.
* 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 and documentation 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.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed or owned by Caldera
* International, Inc.
* 4. Neither the name of Caldera International, Inc. nor the names of other
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* USE OF THE SOFTWARE PROVIDED FOR UNDER THIS LICENSE BY CALDERA
* INTERNATIONAL, INC. 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 CALDERA INTERNATIONAL, INC. 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.
*/
/*
* @(#)bc.library 5.1 (Berkeley) 4/17/91
*/
scale = 20
define e(x) {
auto a, b, c, d, e, g, t, w, y, r
r = ibase
ibase = A
t = scale
scale = 0
if (x > 0) scale = (0.435*x)/1
scale = scale + t + length(scale + t) + 1
w = 0
if (x < 0) {
x = -x
w = 1
}
y = 0
while (x > 2) {
x = x/2
y = y + 1
}
a = 1
b = 1
c = b
d = 1
e = 1
for (a = 1; 1 == 1; a++) {
b = b*x
c = c*a + b
d = d*a
g = c/d
if (g == e) {
g = g/1
while (y--) {
g = g*g
}
scale = t
ibase = r
if (w == 1) return (1/g)
return (g/1)
}
e = g
}
}
define l(x) {
auto a, b, c, d, e, f, g, u, s, t, r
r = ibase
ibase = A
if (x <= 0) {
a = (1 - 10^scale)
ibase = r
return (a)
}
t = scale
f = 1
if (x < 1) {
s = scale(x)
} else {
s = length(x)-scale(x)
}
scale = 0
a = (2.31*s)/1 /* estimated integer part of the answer */
s = t + length(a) + 2 /* estimated length of the answer */
while (x > 2) {
scale = 0
scale = (length(x) + scale(x))/2 + 1
if (scale < s) scale = s
x = sqrt(x)
f = f*2
}
while (x < .5) {
scale = 0
scale = scale(x)/2 + 1
if (scale < s) scale = s
x = sqrt(x)
f = f*2
}
scale = 0
scale = t + length(f) + length((1.05*(t+length(f))/1)) + 1
u = (x - 1)/(x + 1)
s = u*u
scale = t + 2
b = 2*f
c = b
d = 1
e = 1
for (a = 3; 1 == 1 ; a = a + 2) {
b = b*s
c = c*a + d*b
d = d*a
g = c/d
if (g == e) {
scale = t
ibase = r
return (u*c/d)
}
e = g
}
}
define s(x) {
auto a, b, c, s, t, y, p, n, i, r
r = ibase
ibase = A
t = scale
y = x/.7853
s = t + length(y) - scale(y)
if (s < t) s = t
scale = s
p = a(1)
scale = 0
if (x >= 0) n = (x/(2*p) + 1)/2
if (x < 0) n = (x/(2*p) - 1)/2
x = x - 4*n*p
if (n % 2 != 0) x = -x
scale = t + length(1.2*t) - scale(1.2*t)
y = -x*x
a = x
b = 1
s = x
for (i =3 ; 1 == 1; i = i + 2) {
a = a*y
b = b*i*(i - 1)
c = a/b
if (c == 0) {
scale = t
ibase = r
return (s/1)
}
s = s + c
}
}
define c(x) {
auto t, r
r = ibase
ibase = A
t = scale
scale = scale + 1
x = s(x + 2*a(1))
scale = t
ibase = r
return (x/1)
}
define a(x) {
auto a, b, c, d, e, f, g, s, t, r
if (x == 0) return(0)
r = ibase
ibase = A
if (x == 1) {
if (scale < 52) {
a = .7853981633974483096156608458198757210492923498437764/1
ibase = r
return (a)
}
}
t = scale
f = 1
while (x > .5) {
scale = scale + 1
x = -(1 - sqrt(1. + x*x))/x
f = f*2
}
while (x < -.5) {
scale = scale + 1
x = -(1 - sqrt(1. + x*x))/x
f = f*2
}
s = -x*x
b = f
c = f
d = 1
e = 1
for (a = 3; 1 == 1; a = a + 2) {
b = b*s
c = c*a + d*b
d = d*a
g = c/d
if (g == e) {
ibase = r
scale = t
return (x*c/d)
}
e = g
}
}
define j(n,x) {
auto a, b, c, d, e, g, i, s, k, t, r
r = ibase
ibase = A
t = scale
k = 1.36*x + 1.16*t - n
k = length(k) - scale(k)
if (k > 0) scale = scale + k
s = -x*x/4
if (n < 0) {
n = -n
x = -x
}
a = 1
c = 1
for (i = 1; i <= n; i++) {
a = a*x
c = c*2*i
}
b = a
d = 1
e = 1
for (i = 1; 1; i++) {
a = a*s
b = b*i*(n + i) + a
c = c*i*(n + i)
g = b/c
if (g == e) {
ibase = r
scale = t
return (g/1)
}
e = g
}
}
/* vim: set filetype=bc shiftwidth=8 noexpandtab: */