diff options
Diffstat (limited to 'sysdeps/generic/asincos.c')
-rw-r--r-- | sysdeps/generic/asincos.c | 169 |
1 files changed, 0 insertions, 169 deletions
diff --git a/sysdeps/generic/asincos.c b/sysdeps/generic/asincos.c deleted file mode 100644 index c746b1652a..0000000000 --- a/sysdeps/generic/asincos.c +++ /dev/null @@ -1,169 +0,0 @@ -/* - * Copyright (c) 1985, 1993 - * The Regents of the University of California. 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. - * 3. All advertising materials mentioning features or use of this software - * must display the following acknowledgement: - * This product includes software developed by the University of - * California, Berkeley and its contributors. - * 4. Neither the name of the University nor the names of its contributors - * may be used to endorse or promote products derived from this software - * without specific prior written permission. - * - * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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. - */ - -#ifndef lint -static char sccsid[] = "@(#)asincos.c 8.1 (Berkeley) 6/4/93"; -#endif /* not lint */ - -/* ASIN(X) - * RETURNS ARC SINE OF X - * DOUBLE PRECISION (IEEE DOUBLE 53 bits, VAX D FORMAT 56 bits) - * CODED IN C BY K.C. NG, 4/16/85, REVISED ON 6/10/85. - * - * Required system supported functions: - * copysign(x,y) - * sqrt(x) - * - * Required kernel function: - * atan2(y,x) - * - * Method : - * asin(x) = atan2(x,sqrt(1-x*x)); for better accuracy, 1-x*x is - * computed as follows - * 1-x*x if x < 0.5, - * 2*(1-|x|)-(1-|x|)*(1-|x|) if x >= 0.5. - * - * Special cases: - * if x is NaN, return x itself; - * if |x|>1, return NaN. - * - * Accuracy: - * 1) If atan2() uses machine PI, then - * - * asin(x) returns (PI/pi) * (the exact arc sine of x) nearly rounded; - * and PI is the exact pi rounded to machine precision (see atan2 for - * details): - * - * in decimal: - * pi = 3.141592653589793 23846264338327 ..... - * 53 bits PI = 3.141592653589793 115997963 ..... , - * 56 bits PI = 3.141592653589793 227020265 ..... , - * - * in hexadecimal: - * pi = 3.243F6A8885A308D313198A2E.... - * 53 bits PI = 3.243F6A8885A30 = 2 * 1.921FB54442D18 error=.276ulps - * 56 bits PI = 3.243F6A8885A308 = 4 * .C90FDAA22168C2 error=.206ulps - * - * In a test run with more than 200,000 random arguments on a VAX, the - * maximum observed error in ulps (units in the last place) was - * 2.06 ulps. (comparing against (PI/pi)*(exact asin(x))); - * - * 2) If atan2() uses true pi, then - * - * asin(x) returns the exact asin(x) with error below about 2 ulps. - * - * In a test run with more than 1,024,000 random arguments on a VAX, the - * maximum observed error in ulps (units in the last place) was - * 1.99 ulps. - */ - -double asin(x) -double x; -{ - double s,t,copysign(),atan2(),sqrt(),one=1.0; -#if !defined(vax)&&!defined(tahoe) - if(x!=x) return(x); /* x is NaN */ -#endif /* !defined(vax)&&!defined(tahoe) */ - s=copysign(x,one); - if(s <= 0.5) - return(atan2(x,sqrt(one-x*x))); - else - { t=one-s; s=t+t; return(atan2(x,sqrt(s-t*t))); } - -} - -/* ACOS(X) - * RETURNS ARC COS OF X - * DOUBLE PRECISION (IEEE DOUBLE 53 bits, VAX D FORMAT 56 bits) - * CODED IN C BY K.C. NG, 4/16/85, REVISED ON 6/10/85. - * - * Required system supported functions: - * copysign(x,y) - * sqrt(x) - * - * Required kernel function: - * atan2(y,x) - * - * Method : - * ________ - * / 1 - x - * acos(x) = 2*atan2( / -------- , 1 ) . - * \/ 1 + x - * - * Special cases: - * if x is NaN, return x itself; - * if |x|>1, return NaN. - * - * Accuracy: - * 1) If atan2() uses machine PI, then - * - * acos(x) returns (PI/pi) * (the exact arc cosine of x) nearly rounded; - * and PI is the exact pi rounded to machine precision (see atan2 for - * details): - * - * in decimal: - * pi = 3.141592653589793 23846264338327 ..... - * 53 bits PI = 3.141592653589793 115997963 ..... , - * 56 bits PI = 3.141592653589793 227020265 ..... , - * - * in hexadecimal: - * pi = 3.243F6A8885A308D313198A2E.... - * 53 bits PI = 3.243F6A8885A30 = 2 * 1.921FB54442D18 error=.276ulps - * 56 bits PI = 3.243F6A8885A308 = 4 * .C90FDAA22168C2 error=.206ulps - * - * In a test run with more than 200,000 random arguments on a VAX, the - * maximum observed error in ulps (units in the last place) was - * 2.07 ulps. (comparing against (PI/pi)*(exact acos(x))); - * - * 2) If atan2() uses true pi, then - * - * acos(x) returns the exact acos(x) with error below about 2 ulps. - * - * In a test run with more than 1,024,000 random arguments on a VAX, the - * maximum observed error in ulps (units in the last place) was - * 2.15 ulps. - */ - -double acos(x) -double x; -{ - double t,copysign(),atan2(),sqrt(),one=1.0; -#if !defined(vax)&&!defined(tahoe) - if(x!=x) return(x); -#endif /* !defined(vax)&&!defined(tahoe) */ - if( x != -1.0) - t=atan2(sqrt((one-x)/(one+x)),one); - else - t=atan2(one,0.0); /* t = PI/2 */ - return(t+t); -} |