[42] | 1 | <?php // content="text/plain; charset=utf-8" |
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| 2 | require_once ('jpgraph/jpgraph.php'); |
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| 3 | require_once ('jpgraph/jpgraph_scatter.php'); |
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| 4 | require_once ('jpgraph/jpgraph_line.php'); |
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| 5 | require_once ('jpgraph/jpgraph_utils.inc.php'); |
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| 6 | |
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| 7 | // Create some "fake" regression data |
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| 8 | $datay = array(); |
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| 9 | $datax = array(); |
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| 10 | $a= 3.2; |
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| 11 | $b= 2.5; |
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| 12 | for($x=0; $x < 20; ++$x) { |
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| 13 | $datax[$x] = $x; |
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| 14 | $datay[$x] = $a + $b*$x + rand(-20,20); |
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| 15 | } |
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| 16 | |
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| 17 | $lr = new LinearRegression($datax, $datay); |
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| 18 | list( $stderr, $corr ) = $lr->GetStat(); |
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| 19 | list( $xd, $yd ) = $lr->GetY(0,19); |
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| 20 | |
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| 21 | // Create the graph |
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| 22 | $graph = new Graph(300,250); |
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| 23 | $graph->SetScale('linlin'); |
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| 24 | |
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| 25 | // Setup title |
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| 26 | $graph->title->Set("Linear regression"); |
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| 27 | $graph->title->SetFont(FF_ARIAL,FS_BOLD,14); |
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| 28 | |
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| 29 | $graph->subtitle->Set('(stderr='.sprintf('%.2f',$stderr).', corr='.sprintf('%.2f',$corr).')'); |
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| 30 | $graph->subtitle->SetFont(FF_ARIAL,FS_NORMAL,12); |
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| 31 | |
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| 32 | // make sure that the X-axis is always at the |
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| 33 | // bottom at the plot and not just at Y=0 which is |
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| 34 | // the default position |
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| 35 | $graph->xaxis->SetPos('min'); |
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| 36 | |
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| 37 | // Create the scatter plot with some nice colors |
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| 38 | $sp1 = new ScatterPlot($datay,$datax); |
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| 39 | $sp1->mark->SetType(MARK_FILLEDCIRCLE); |
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| 40 | $sp1->mark->SetFillColor("red"); |
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| 41 | $sp1->SetColor("blue"); |
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| 42 | $sp1->SetWeight(3); |
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| 43 | $sp1->mark->SetWidth(4); |
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| 44 | |
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| 45 | // Create the regression line |
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| 46 | $lplot = new LinePlot($yd); |
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| 47 | $lplot->SetWeight(2); |
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| 48 | $lplot->SetColor('navy'); |
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| 49 | |
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| 50 | // Add the pltos to the line |
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| 51 | $graph->Add($sp1); |
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| 52 | $graph->Add($lplot); |
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| 53 | |
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| 54 | // ... and stroke |
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| 55 | $graph->Stroke(); |
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| 56 | |
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| 57 | ?> |
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| 58 | |
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| 59 | |
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