access-nbody.html (5796B)
1 <!DOCTYPE html> 2 <head> 3 <!-- 4 Copyright (C) 2007 Apple Inc. All rights reserved. 5 6 Redistribution and use in source and binary forms, with or without 7 modification, are permitted provided that the following conditions 8 are met: 9 1. Redistributions of source code must retain the above copyright 10 notice, this list of conditions and the following disclaimer. 11 2. Redistributions in binary form must reproduce the above copyright 12 notice, this list of conditions and the following disclaimer in the 13 documentation and/or other materials provided with the distribution. 14 15 THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY 16 EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17 IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 18 PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE COMPUTER, INC. OR 19 CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 20 EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 21 PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 22 PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY 23 OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 24 (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 25 OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26 --> 27 28 <title>SunSpider access-nbody</title> 29 30 </head> 31 32 <body> 33 <h3>access-nbody</h3> 34 <div id="console"> 35 </div> 36 37 <script> 38 39 var _sunSpiderStartDate = new Date(); 40 41 /* The Great Computer Language Shootout 42 http://shootout.alioth.debian.org/ 43 contributed by Isaac Gouy */ 44 45 var PI = 3.141592653589793; 46 var SOLAR_MASS = 4 * PI * PI; 47 var DAYS_PER_YEAR = 365.24; 48 49 function Body(x,y,z,vx,vy,vz,mass){ 50 this.x = x; 51 this.y = y; 52 this.z = z; 53 this.vx = vx; 54 this.vy = vy; 55 this.vz = vz; 56 this.mass = mass; 57 } 58 59 Body.prototype.offsetMomentum = function(px,py,pz) { 60 this.vx = -px / SOLAR_MASS; 61 this.vy = -py / SOLAR_MASS; 62 this.vz = -pz / SOLAR_MASS; 63 return this; 64 } 65 66 function Jupiter(){ 67 return new Body( 68 4.84143144246472090e+00, 69 -1.16032004402742839e+00, 70 -1.03622044471123109e-01, 71 1.66007664274403694e-03 * DAYS_PER_YEAR, 72 7.69901118419740425e-03 * DAYS_PER_YEAR, 73 -6.90460016972063023e-05 * DAYS_PER_YEAR, 74 9.54791938424326609e-04 * SOLAR_MASS 75 ); 76 } 77 78 function Saturn(){ 79 return new Body( 80 8.34336671824457987e+00, 81 4.12479856412430479e+00, 82 -4.03523417114321381e-01, 83 -2.76742510726862411e-03 * DAYS_PER_YEAR, 84 4.99852801234917238e-03 * DAYS_PER_YEAR, 85 2.30417297573763929e-05 * DAYS_PER_YEAR, 86 2.85885980666130812e-04 * SOLAR_MASS 87 ); 88 } 89 90 function Uranus(){ 91 return new Body( 92 1.28943695621391310e+01, 93 -1.51111514016986312e+01, 94 -2.23307578892655734e-01, 95 2.96460137564761618e-03 * DAYS_PER_YEAR, 96 2.37847173959480950e-03 * DAYS_PER_YEAR, 97 -2.96589568540237556e-05 * DAYS_PER_YEAR, 98 4.36624404335156298e-05 * SOLAR_MASS 99 ); 100 } 101 102 function Neptune(){ 103 return new Body( 104 1.53796971148509165e+01, 105 -2.59193146099879641e+01, 106 1.79258772950371181e-01, 107 2.68067772490389322e-03 * DAYS_PER_YEAR, 108 1.62824170038242295e-03 * DAYS_PER_YEAR, 109 -9.51592254519715870e-05 * DAYS_PER_YEAR, 110 5.15138902046611451e-05 * SOLAR_MASS 111 ); 112 } 113 114 function Sun(){ 115 return new Body(0.0, 0.0, 0.0, 0.0, 0.0, 0.0, SOLAR_MASS); 116 } 117 118 119 function NBodySystem(bodies){ 120 this.bodies = bodies; 121 var px = 0.0; 122 var py = 0.0; 123 var pz = 0.0; 124 var size = this.bodies.length; 125 for (var i=0; i<size; i++){ 126 var b = this.bodies[i]; 127 var m = b.mass; 128 px += b.vx * m; 129 py += b.vy * m; 130 pz += b.vz * m; 131 } 132 this.bodies[0].offsetMomentum(px,py,pz); 133 } 134 135 NBodySystem.prototype.advance = function(dt){ 136 var dx, dy, dz, distance, mag; 137 var size = this.bodies.length; 138 139 for (var i=0; i<size; i++) { 140 var bodyi = this.bodies[i]; 141 for (var j=i+1; j<size; j++) { 142 var bodyj = this.bodies[j]; 143 dx = bodyi.x - bodyj.x; 144 dy = bodyi.y - bodyj.y; 145 dz = bodyi.z - bodyj.z; 146 147 distance = Math.sqrt(dx*dx + dy*dy + dz*dz); 148 mag = dt / (distance * distance * distance); 149 150 bodyi.vx -= dx * bodyj.mass * mag; 151 bodyi.vy -= dy * bodyj.mass * mag; 152 bodyi.vz -= dz * bodyj.mass * mag; 153 154 bodyj.vx += dx * bodyi.mass * mag; 155 bodyj.vy += dy * bodyi.mass * mag; 156 bodyj.vz += dz * bodyi.mass * mag; 157 } 158 } 159 160 for (var i=0; i<size; i++) { 161 var body = this.bodies[i]; 162 body.x += dt * body.vx; 163 body.y += dt * body.vy; 164 body.z += dt * body.vz; 165 } 166 } 167 168 NBodySystem.prototype.energy = function(){ 169 var dx, dy, dz, distance; 170 var e = 0.0; 171 var size = this.bodies.length; 172 173 for (var i=0; i<size; i++) { 174 var bodyi = this.bodies[i]; 175 176 e += 0.5 * bodyi.mass * 177 ( bodyi.vx * bodyi.vx 178 + bodyi.vy * bodyi.vy 179 + bodyi.vz * bodyi.vz ); 180 181 for (var j=i+1; j<size; j++) { 182 var bodyj = this.bodies[j]; 183 dx = bodyi.x - bodyj.x; 184 dy = bodyi.y - bodyj.y; 185 dz = bodyi.z - bodyj.z; 186 187 distance = Math.sqrt(dx*dx + dy*dy + dz*dz); 188 e -= (bodyi.mass * bodyj.mass) / distance; 189 } 190 } 191 return e; 192 } 193 194 var ret; 195 196 for ( var n = 3; n <= 24; n *= 2 ) { 197 (function(){ 198 var bodies = new NBodySystem( Array( 199 Sun(),Jupiter(),Saturn(),Uranus(),Neptune() 200 )); 201 var max = n * 100; 202 203 ret = bodies.energy(); 204 for (var i=0; i<max; i++){ 205 bodies.advance(0.01); 206 } 207 ret = bodies.energy(); 208 })(); 209 } 210 211 212 var _sunSpiderInterval = new Date() - _sunSpiderStartDate; 213 214 document.getElementById("console").innerHTML = _sunSpiderInterval; 215 </script> 216 217 218 </body> 219 </html>