Random walks: Difference between revisions
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A WASSERMANN (talk | contribs) No edit summary |
A WASSERMANN (talk | contribs) No edit summary |
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<option value="100">100</option> | <option value="100">100</option> | ||
<option value="200">200</option> | <option value="200">200</option> | ||
</select> | </select> <br /> | ||
<input type="button" value="run" onClick="run()"> | <input type="button" value="run" onClick="run()"> | ||
<input type="button" value="clear" onClick="clearturtle()"> | <input type="button" value="clear" onClick="clearturtle()"> | ||
<br /> | <br /> | ||
</form></html> | |||
We have set <i>stepsize=5</i> and <i>Number of steps per walk = 100</i>. Therefore, the expected | |||
squared distance from the starting point will be <math>100\cdot 5^2=2500</math>. | |||
<html> | |||
<form> | |||
Average square of the distance between starting point and endpoint of the walks: <input type="text" value="" id="output"> | Average square of the distance between starting point and endpoint of the walks: <input type="text" value="" id="output"> | ||
</form> | </form> | ||
Revision as of 13:07, 27 May 2009
We have set stepsize=5 and Number of steps per walk = 100. Therefore, the expected squared distance from the starting point will be [math]\displaystyle{ 100\cdot 5^2=2500 }[/math].
Source code
<jsxgraph width="600" height="600">
var brd = JXG.JSXGraph.initBoard('jxgbox', {originX: 300, originY: 300, unitX: 3, unitY: 3});
var t = brd.createElement('turtle');
function run() {
var i,j,dist,sumdist=0.0;
var stepSize = 5;
brd.suspendUpdate();
var nr = $('number').value*1;
for (i=0;i<nr;i++) {
for (j=0;j<100;j++) {
var a = Math.floor(360*Math.random());
t.right(a);
t.forward(stepSize);
}
dist = t.pos[0]*t.pos[0]+t.pos[1]*t.pos[1];
sumdist += dist;
t.home();
}
$('output').value = (sumdist/nr).toFixed(3);
brd.unsuspendUpdate();
}
function clearturtle() {
sumist = 0.0
t.cs();
}
</jsxgraph>
