| s_asinh.c (22993) | s_asinh.c (23579) |
|---|---|
| 1/* @(#)s_asinh.c 5.1 93/09/24 */ 2/* 3 * ==================================================== 4 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. 5 * 6 * Developed at SunPro, a Sun Microsystems, Inc. business. 7 * Permission to use, copy, modify, and distribute this 8 * software is freely granted, provided that this notice 9 * is preserved. 10 * ==================================================== 11 */ 12 13#ifndef lint | 1/* @(#)s_asinh.c 5.1 93/09/24 */ 2/* 3 * ==================================================== 4 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. 5 * 6 * Developed at SunPro, a Sun Microsystems, Inc. business. 7 * Permission to use, copy, modify, and distribute this 8 * software is freely granted, provided that this notice 9 * is preserved. 10 * ==================================================== 11 */ 12 13#ifndef lint |
| 14static char rcsid[] = "$Id$"; | 14static char rcsid[] = "$Id: s_asinh.c,v 1.4 1997/02/22 15:10:56 peter Exp $"; |
| 15#endif 16 17/* asinh(x) 18 * Method : 19 * Based on 20 * asinh(x) = sign(x) * log [ |x| + sqrt(x*x+1) ] 21 * we have 22 * asinh(x) := x if 1+x*x=1, --- 28 unchanged lines hidden (view full) --- 51 if(ix>=0x7ff00000) return x+x; /* x is inf or NaN */ 52 if(ix< 0x3e300000) { /* |x|<2**-28 */ 53 if(huge+x>one) return x; /* return x inexact except 0 */ 54 } 55 if(ix>0x41b00000) { /* |x| > 2**28 */ 56 w = __ieee754_log(fabs(x))+ln2; 57 } else if (ix>0x40000000) { /* 2**28 > |x| > 2.0 */ 58 t = fabs(x); | 15#endif 16 17/* asinh(x) 18 * Method : 19 * Based on 20 * asinh(x) = sign(x) * log [ |x| + sqrt(x*x+1) ] 21 * we have 22 * asinh(x) := x if 1+x*x=1, --- 28 unchanged lines hidden (view full) --- 51 if(ix>=0x7ff00000) return x+x; /* x is inf or NaN */ 52 if(ix< 0x3e300000) { /* |x|<2**-28 */ 53 if(huge+x>one) return x; /* return x inexact except 0 */ 54 } 55 if(ix>0x41b00000) { /* |x| > 2**28 */ 56 w = __ieee754_log(fabs(x))+ln2; 57 } else if (ix>0x40000000) { /* 2**28 > |x| > 2.0 */ 58 t = fabs(x); |
| 59 w = __ieee754_log(2.0*t+one/(sqrt(x*x+one)+t)); | 59 w = __ieee754_log(2.0*t+one/(__ieee754_sqrt(x*x+one)+t)); |
| 60 } else { /* 2.0 > |x| > 2**-28 */ 61 t = x*x; | 60 } else { /* 2.0 > |x| > 2**-28 */ 61 t = x*x; |
| 62 w =log1p(fabs(x)+t/(one+sqrt(one+t))); | 62 w =log1p(fabs(x)+t/(one+__ieee754_sqrt(one+t))); |
| 63 } 64 if(hx>0) return w; else return -w; 65} | 63 } 64 if(hx>0) return w; else return -w; 65} |