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/* -*- Mode: C; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
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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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* 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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* 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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* The Original Code is Mozilla Communicator client code, released
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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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* 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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* ***** END LICENSE BLOCK ***** */
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/* @(#)k_sin.c 1.3 95/01/18 */
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* ====================================================
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* Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
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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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* ====================================================
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/* __kernel_sin( x, y, iy)
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* kernel sin function on [-pi/4, pi/4], pi/4 ~ 0.7854
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* Input x is assumed to be bounded by ~pi/4 in magnitude.
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* Input y is the tail of x.
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* Input iy indicates whether y is 0. (if iy=0, y assume to be 0).
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* 1. Since sin(-x) = -sin(x), we need only to consider positive x.
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* 2. if x < 2^-27 (hx<0x3e400000 0), return x with inexact if x!=0.
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* 3. sin(x) is approximated by a polynomial of degree 13 on
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* sin(x) ~ x + S1*x + ... + S6*x
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* |sin(x) 2 4 6 8 10 12 | -58
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* |----- - (1+S1*x +S2*x +S3*x +S4*x +S5*x +S6*x )| <= 2
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* 4. sin(x+y) = sin(x) + sin'(x')*y
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* ~ sin(x) + (1-x*x/2)*y
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* For better accuracy, let
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* r = x *(S2+x *(S3+x *(S4+x *(S5+x *S6))))
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* sin(x) = x + (S1*x + (x *(r-y/2)+y))
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half = 5.00000000000000000000e-01, /* 0x3FE00000, 0x00000000 */
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S1 = -1.66666666666666324348e-01, /* 0xBFC55555, 0x55555549 */
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S2 = 8.33333333332248946124e-03, /* 0x3F811111, 0x1110F8A6 */
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S3 = -1.98412698298579493134e-04, /* 0xBF2A01A0, 0x19C161D5 */
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S4 = 2.75573137070700676789e-06, /* 0x3EC71DE3, 0x57B1FE7D */
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S5 = -2.50507602534068634195e-08, /* 0xBE5AE5E6, 0x8A2B9CEB */
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S6 = 1.58969099521155010221e-10; /* 0x3DE5D93A, 0x5ACFD57C */
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double __kernel_sin(double x, double y, int iy)
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double __kernel_sin(x, y, iy)
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double x,y; int iy; /* iy=0 if y is zero */
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ix = __HI(u)&0x7fffffff; /* high word of x */
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if(ix<0x3e400000) /* |x| < 2**-27 */
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{if((int)x==0) return x;} /* generate inexact */
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r = S2+z*(S3+z*(S4+z*(S5+z*S6)));
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if(iy==0) return x+v*(S1+z*r);
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else return x-((z*(half*y-v*r)-y)-v*S1);
added
removed
src/dom/js/fdlibm/k_sin.c
