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/* * Mode: C; tabwidth: 8; indenttabsmode: nil; cbasicoffset: 4 * 
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* 
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* ***** BEGIN LICENSE BLOCK ***** 
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* Version: MPL 1.1/GPL 2.0/LGPL 2.1 
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* 
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* The contents of this file are subject to the Mozilla Public License Version 
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* 1.1 (the "License"); you may not use this file except in compliance with 
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* the License. You may obtain a copy of the License at 
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* http://www.mozilla.org/MPL/ 
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* 
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* Software distributed under the License is distributed on an "AS IS" basis, 
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* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License 
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* for the specific language governing rights and limitations under the 
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* License. 
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* 
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* The Original Code is Mozilla Communicator client code, released 
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* March 31, 1998. 
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* 
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* The Initial Developer of the Original Code is 
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* Sun Microsystems, Inc. 
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* Portions created by the Initial Developer are Copyright (C) 1998 
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* the Initial Developer. All Rights Reserved. 
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* 
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* Contributor(s): 
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* 
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* Alternatively, the contents of this file may be used under the terms of 
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* either of the GNU General Public License Version 2 or later (the "GPL"), 
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* or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"), 
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* in which case the provisions of the GPL or the LGPL are applicable instead 
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* of those above. If you wish to allow use of your version of this file only 
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* under the terms of either the GPL or the LGPL, and not to allow others to 
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* use your version of this file under the terms of the MPL, indicate your 
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* decision by deleting the provisions above and replace them with the notice 
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* and other provisions required by the GPL or the LGPL. If you do not delete 
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* the provisions above, a recipient may use your version of this file under 
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* the terms of any one of the MPL, the GPL or the LGPL. 
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* 
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* ***** END LICENSE BLOCK ***** */ 
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/* @(#)e_sinh.c 1.3 95/01/18 */ 
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/* 
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* ==================================================== 
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* Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. 
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* 
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* Developed at SunSoft, a Sun Microsystems, Inc. business. 
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* Permission to use, copy, modify, and distribute this 
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* software is freely granted, provided that this notice 
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* is preserved. 
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* ==================================================== 
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*/ 
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/* __ieee754_sinh(x) 
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* Method : 
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* mathematically sinh(x) if defined to be (exp(x)exp(x))/2 
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* 1. Replace x by x (sinh(x) = sinh(x)). 
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* 2. 
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* E + E/(E+1) 
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* 0 <= x <= 22 : sinh(x) := , E=expm1(x) 
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* 2 
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* 
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* 22 <= x <= lnovft : sinh(x) := exp(x)/2 
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* lnovft <= x <= ln2ovft: sinh(x) := exp(x/2)/2 * exp(x/2) 
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* ln2ovft < x : sinh(x) := x*shuge (overflow) 
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* 
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* Special cases: 
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* sinh(x) is x if x is +INF, INF, or NaN. 
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* only sinh(0)=0 is exact for finite x. 
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*/ 
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#include "fdlibm.h" 
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#ifdef __STDC__ 
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static const double one = 1.0, shuge = 1.0e307; 
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#else 
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static double one = 1.0, shuge = 1.0e307; 
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#endif 
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#ifdef __STDC__ 
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double __ieee754_sinh(double x) 
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#else 
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double __ieee754_sinh(x) 
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double x; 
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#endif 
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{ 
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fd_twoints u; 
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double t,w,h; 
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int ix,jx; 
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unsigned lx; 
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/* High word of x. */ 
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u.d = x; 
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jx = __HI(u); 
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ix = jx&0x7fffffff; 
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/* x is INF or NaN */ 
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if(ix>=0x7ff00000) return x+x; 
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h = 0.5; 
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if (jx<0) h = h; 
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/* x in [0,22], return sign(x)*0.5*(E+E/(E+1))) */ 
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if (ix < 0x40360000) { /* x<22 */ 
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if (ix<0x3e300000) /* x<2**28 */ 
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if(shuge+x>one) return x;/* sinh(tiny) = tiny with inexact */ 
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t = fd_expm1(fd_fabs(x)); 
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if(ix<0x3ff00000) return h*(2.0*tt*t/(t+one)); 
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return h*(t+t/(t+one)); 
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} 
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/* x in [22, log(maxdouble)] return 0.5*exp(x) */ 
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if (ix < 0x40862E42) return h*__ieee754_exp(fd_fabs(x)); 
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/* x in [log(maxdouble), overflowthresold] */ 
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lx = *( (((*(unsigned*)&one)>>29)) + (unsigned*)&x); 
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if (ix<0x408633CE  (ix==0x408633ce)&&(lx<=(unsigned)0x8fb9f87d)) { 
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w = __ieee754_exp(0.5*fd_fabs(x)); 
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t = h*w; 
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return t*w; 
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} 
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/* x > overflowthresold, sinh(x) overflow */ 
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return x*shuge; 
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} 