Difference between revisions of "Polynomial regression II"

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Here are 30 randomly distributed points. The range of these points can be adjusted by the slider 'scale'.
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Through these points a regression polynomial is computed. The degree of this polynomial can be adjusted by the slider 'degree'.
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<jsxgraph width="700" height="500">
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brd = JXG.JSXGraph.initBoard('jxgbox', {boundingbox:[-2, 100, 220, -70], grid: false, axis:true});
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brd.suspendUpdate();
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deg = brd.createElement('slider',[[10,90],[100,90],[1,1,10]],{name:'degree',snapWidth:1});   
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s = brd.createElement('slider',[[10,70],[100,70],[0,1,3]],{name:'scale'});   
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pointlist = [];
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for (i=0; i<30;i++) {
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    pointlist.push(brd.createElement('point', [function() { return 200*Math.random(); }, function() { return s.Value()*30*Math.random()+20;}], { style:4, strokecolor:"#0000a0", name:" "}));
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}
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regression = JXG.Math.Numerics.regressionPolynomial(deg,pointlist);
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reg = brd.createElement('functiongraph',[regression],{strokeColor:'green'});   
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t = brd.createElement('text',[20,-40,
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            function(){ return "r(x) = " + regression.getTerm();}
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            ],
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            {strokeColor:'black',fontSize:'14px'});   
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brd.unsuspendUpdate();
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</jsxgraph>
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===The underlying JavaScript code===
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<source lang="xml">
 
<jsxgraph width="700" height="500">
 
<jsxgraph width="700" height="500">
 
brd = JXG.JSXGraph.initBoard('jxgbox', {boundingbox:[-2, 100, 220, -70], grid: false, axis:true});
 
brd = JXG.JSXGraph.initBoard('jxgbox', {boundingbox:[-2, 100, 220, -70], grid: false, axis:true});
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brd.unsuspendUpdate();
 
brd.unsuspendUpdate();
 
</jsxgraph>
 
</jsxgraph>
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</source>
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 +
[[Category:Examples]]

Revision as of 16:20, 19 August 2009

Here are 30 randomly distributed points. The range of these points can be adjusted by the slider 'scale'. Through these points a regression polynomial is computed. The degree of this polynomial can be adjusted by the slider 'degree'.

The underlying JavaScript code

<jsxgraph width="700" height="500">
brd = JXG.JSXGraph.initBoard('jxgbox', {boundingbox:[-2, 100, 220, -70], grid: false, axis:true});
brd.suspendUpdate();
deg = brd.createElement('slider',[[10,90],[100,90],[1,1,10]],{name:'degree',snapWidth:1});     
s = brd.createElement('slider',[[10,70],[100,70],[0,1,3]],{name:'scale'});     
pointlist = [];
for (i=0; i<30;i++) {
    pointlist.push(brd.createElement('point', [function() { return 200*Math.random(); }, function() { return s.Value()*30*Math.random()+20;}], { style:4, strokecolor:"#0000a0", name:" "})); 
}

regression = JXG.Math.Numerics.regressionPolynomial(deg,pointlist); 
reg = brd.createElement('functiongraph',[regression],{strokeColor:'green'});     
t = brd.createElement('text',[20,-40,
            function(){ return "r(x) = " + regression.getTerm();}
            ],
            {strokeColor:'black',fontSize:'14px'});     

brd.unsuspendUpdate();
</jsxgraph>