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<html>
<head>
<title>Simson Steiner | JSXGraph Example</title>
<link rel="stylesheet" type="text/css" href="../../distrib/jsxgraph.css" />
<script type="text/javascript" src="../../distrib/jsxgraphcore.js"></script>
<script type="text/javascript" src="../../src/Triangle.js"></script>
</head>
<body>
<div id="debug" style="display: none"></div>
<center>
<div style="width: 1000px;">
<div style="width:600px; height: 510px;">
<div id="jxgbox" class="jxgbox" style="width:600px; height:500px; text-align: left; float: left;"></div>
<div id="polynomials" style="display: none; width: 600px; height: 500px; margin-left: 10px; text-align: left; padding-left: -200px;"></div>
</div>
<div style="width: 800px; margin-top: 10px;">
<form>
<input type="button" onclick="calculateLocus();" value="Calculate locus of X" />
<input type="button" onclick="showLocusEquation();" value="Show locus equation" />
<input type="button" onclick="showBoard();" value="Show board" />
<input type="button" onclick="showLocusTime(loc)" value="Show locus time" />
</form>
</div>
</div>
</center>
<script type="text/javascript">
/* <![CDATA[ */
board = JXG.JSXGraph.initBoard('jxgbox', {boundingbox:[-4, 6, 8, -4], axis: true, grid: false,
keepaspectratio: true, showcopyright: true});
p1 = board.create('point', [0, 0], {name: 'A'});
p2 = board.create('point', [6, 0], {name: 'B'});
p3 = board.create('point', [4, 4], {name: 'C'});
t1 = board.create('triangle', [p1, p2, p3], {strokeWidth: '1px', withLabel: true});
m1 = board.create('point', [4, 1.5], {name:"X", color:'green'});
l1 = board.createElement('perpendicularpoint', [m1, t1.c], {name: 'L', color: 'blue'});
l2 = board.createElement('perpendicularpoint', [m1, t1.a], {name: 'M', color: 'blue'});
l3 = board.createElement('perpendicularpoint', [m1, t1.b], {name: 'N', color: 'blue'});
t2 = board.createElement('triangle', [l1, l2, l3], {strokeWidth: '1px', withLabel: true});
t1.a.setProperty({withLabel: false});
t1.b.setProperty({withLabel: false});
t1.c.setProperty({withLabel: false});
t2.a.setProperty({withLabel: false});
t2.b.setProperty({withLabel: false});
t2.c.setProperty({withLabel: false});
// Get area of triangle given by the three points A, B, C
getTriangleArea = function(A, B, C, square) {
var a = B.coords.distance(JXG.COORDS_BY_USER, C.coords),
b = A.coords.distance(JXG.COORDS_BY_USER, C.coords),
c = B.coords.distance(JXG.COORDS_BY_USER, A.coords),
s = (typeof square == 'undefined' ? true : square);
if (s)
return (4*a*a*c*c-(a*a+c*c-b*b)*(a*a+c*c-b*b));
else
return Math.sqrt((4*a*a*c*c-(a*a+c*c-b*b)*(a*a+c*c-b*b))/16.);
};
te = board.createElement('text', [-3.8, 5.5, function () { return ("Fläche des Dreiecks EDF: " + getTriangleArea(l1, l2, l3, false)); }]);
// dependency and polynomial generation hacking
m1.ancestors[l1.id] = l1;
m1.ancestors[l2.id] = l2;
m1.ancestors[l3.id] = l3;
m1.ancestors[p1.id] = p1;
m1.ancestors[p2.id] = p2;
m1.ancestors[p3.id] = p3;
m1.generatePolynomial = function () {
var as16 = getTriangleArea(l1, l2, l3),
as = '((('+l2.symbolic.x+')-('+l3.symbolic.x+'))^2+(('+l2.symbolic.y+')-('+l3.symbolic.y+'))^2)',
bs = '((('+l1.symbolic.x+')-('+l3.symbolic.x+'))^2+(('+l1.symbolic.y+')-('+l3.symbolic.y+'))^2)',
cs = '((('+l2.symbolic.x+')-('+l1.symbolic.x+'))^2+(('+l2.symbolic.y+')-('+l1.symbolic.y+'))^2)',
poly = '4*'+as+'*'+cs+'-('+as+'+'+cs+'-'+bs+')*('+as+'+'+cs+'-'+bs+')-('+as16+')';
return ['4*'+as+'*'+cs+'-('+as+'+'+cs+'-'+bs+')*('+as+'+'+cs+'-'+bs+')-('+as16+')'];
};
loc = null;
createControlElements = function () {
glider = board.createElement('glider', [0, 5, loc]);
lg1 = board.createElement('perpendicularpoint', [glider, t1.a]);
lg2 = board.createElement('perpendicularpoint', [glider, t1.b]);
lg3 = board.createElement('perpendicularpoint', [glider, t1.c]);
tecontrol = board.createElement('text', [-3.8, 5, function () { return ("Fläche des Dreiecks HIJ: " + getTriangleArea(lg1, lg2, lg3, false)); }]);
};
function calculateLocus() {
loc = board.create('locus', [m1], {strokeColor: 'black', strokeWidth: '2px'});
}
function showLocusEquation() {
var out = document.getElementById('polynomials');
out.innerHTML = '<ul>';
for(i=0; i<loc.eq.length; i++)
out.innerHTML += '<li>' + loc.eq[i] + ' = 0</li>';
out.innerHTML += '</ul>';
out.style.display = 'block';
document.getElementById('jxgbox').style.display = 'none';
}
function showBoard() {
document.getElementById('polynomials').style.display = 'none';
document.getElementById('jxgbox').style.display = 'block';
}
function dimConstruction() {
var c = [p3, p4, c1, g, p6, c2, p14_1], i, o = getDim();
if(p3.visProp['strokeOpacity'] == o)
o = 1.0;
for(i=0; i<c.length; i++) {
c[i].setProperty({strokeOpacity: o, fillOpacity: o});
}
}
function showLocusTime(l) {
document.getElementById('polynomials').style.display = 'block';
document.getElementById('jxgbox').style.display = 'none';
document.getElementById('polynomials').innerHTML = l.ctime;
}
function toggleOptimize() {
if(opt) {
board.options.locus.translateToOrigin = false;
board.options.locus.translateTo10 = false;
opt = false;
document.getElementById('opt').value = "Optimization is off";
} else {
board.options.locus.translateToOrigin = true;
board.options.locus.translateTo10 = true;
opt = true;
document.getElementById('opt').value = "Optimization is on";
}
}
/* ]]> */
</script>
<br/>
</body>
</html>
|
