Lagrange interpolation (dup): Difference between revisions
From JSXGraph Wiki
A WASSERMANN (talk | contribs) No edit summary |
A WASSERMANN (talk | contribs) No edit summary |
||
| Line 4: | Line 4: | ||
<link rel="stylesheet" type="text/css" href="http://jsxgraph.uni-bayreuth.de/distrib/jsxgraph.css" /> | <link rel="stylesheet" type="text/css" href="http://jsxgraph.uni-bayreuth.de/distrib/jsxgraph.css" /> | ||
<script type="text/javascript" src="http://jsxgraph.uni-bayreuth.de/distrib/prototype.js"></script> | <script type="text/javascript" src="http://jsxgraph.uni-bayreuth.de/distrib/prototype.js"></script> | ||
<script type="text/javascript" src="http://jsxgraph.uni-bayreuth.de/distrib/jsxgraphcore.js"></script> | <!--<script type="text/javascript" src="http://jsxgraph.uni-bayreuth.de/distrib/jsxgraphcore.js"></script>--> | ||
<script type="text/javascript" src="http://jsxgraph.uni-bayreuth.de/~alfred/jsxgraph/branches/0.70/src/loadjsxgraph.js"></script> | |||
<form><input type="button" value="Add point" onClick="addPoint()"></form> | <form><input type="button" value="Add point" onClick="addPoint()"></form> | ||
<div id="box" class="jxgbox" style="width:600px; height:400px;"></div> | <div id="box" class="jxgbox" style="width:600px; height:400px;"></div> | ||
Revision as of 22:09, 10 December 2008
Constructs a polynomial of degree n through n+1 given points. Points can be added by clicking on "Add point".
board = JXG.JSXGraph.initBoard('box', {originX: 250, originY: 250, unitX: 50, unitY: 25});
// Axes
b1axisx = board.createElement('axis', [[0,0], [1,0]], {});
b1axisy = board.createElement('axis', [[0,0], [0,1]], {});
var p = [];
p[0] = board.createElement('point', [-1,2], {style:6});
p[1] = board.createElement('point', [3,-1], {style:6});
var polynomial = function(x) {
var y = 0.0;
for (var i=0;i<p.length;i++) {
var t = p[i].Y();
for (var k=0;k<p.length;k++) {
if (k!=i) {
t *= (x-p[k].X())/(p[i].X()-p[k].X());
}
}
y += t;
}
return y;
};
graph = board.createElement('curve', ['x', polynomial, 'x', -10, 10], {curveType:'graph'});
function addPoint() {
p.push(board.createElement('point',[(Math.random()-0.5)*10,(Math.random()-0.5)*3],{style:6}));
board.update();
}
