Difference between revisions of "Even simpler function plotter"
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Jump to navigationJump to searchA WASSERMANN (talk | contribs) |
A WASSERMANN (talk | contribs) |
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| Line 28: | Line 28: | ||
JXG.JSXGraph.freeBoard(board); | JXG.JSXGraph.freeBoard(board); | ||
board = JXG.JSXGraph.initBoard('jxgbox', {boundingbox:[-5,8,8,-5], axis:true}); | board = JXG.JSXGraph.initBoard('jxgbox', {boundingbox:[-5,8,8,-5], axis:true}); | ||
| + | f = null; | ||
| + | curve = null; | ||
} | } | ||
function addTangent() { | function addTangent() { | ||
| − | board.suspendUpdate(); | + | if (JXG.isFunction(f)) { |
| − | + | board.suspendUpdate(); | |
| − | + | var p = board.create('glider',[0,0,curve], {name:'drag me'}); | |
| − | + | board.create('tangent',[p], {name:'drag me'}); | |
| + | board.unsuspendUpdate(); | ||
| + | } | ||
} | } | ||
Revision as of 16:06, 15 July 2010
The underlying JavaScript code
<input type="text" id="input" value="sin(x)*x">
<input type="button" value="plot" onClick="plotter()">
<input type="button" value="clear all" onClick="clearAll()">
var board = JXG.JSXGraph.initBoard('jxgbox', {boundingbox:[-5,8,8,-5], axis:true});
function plotter() {
var t = JXG.GeonextParser.geonext2JS(document.getElementById('input').value);
var f = new Function('x','var y = '+t+'; return y;');
board.create('functiongraph',[f,
function(){
var c = new JXG.Coords(JXG.COORDS_BY_SCREEN,[0,0],board);
return c.usrCoords[1];
},
function(){
var c = new JXG.Coords(JXG.COORDS_BY_SCREEN,[board.canvasWidth,0],board);
return c.usrCoords[1];
}
]);
}
function clearAll() {
JXG.JSXGraph.freeBoard(board);
board = JXG.JSXGraph.initBoard('jxgbox', {boundingbox:[-5,8,8,-5], axis:true});
}
