54 lines
1.1 KiB
PHP
54 lines
1.1 KiB
PHP
<?php
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include ("../jpgraph.php");
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include ("../jpgraph_scatter.php");
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include ("../jpgraph_line.php");
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// Create some "fake" regression data
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$datay = array();
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$datay2 = array();
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$datax = array();
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$a=rand(-3,3);
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$b=rand(-5,5);
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for($x=0; $x<20; ++$x) {
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$datay[] = $a*$x + $b;
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$datay2[] = $a*$x + $b + rand(-30,30);
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$datax[] = $x;
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}
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// Create the graph
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$graph = new Graph(300,200,'auto');
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$graph->SetScale("linlin");
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// Setup title
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$graph->title->Set("Example of linear regression");
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$graph->title->SetFont(FF_FONT1,FS_BOLD);
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// make sure that the X-axis is always at the
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// bottom at the plot and not just at Y=0 which is
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// the default position
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$graph->xaxis->SetPos('min');
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// Create the scatter plot with some nice colors
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$sp1 = new ScatterPlot($datay2,$datax);
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$sp1->mark->SetType(MARK_FILLEDCIRCLE);
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$sp1->mark->SetFillColor("red");
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$sp1->SetColor("blue");
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$sp1->SetWeight(3);
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$sp1->mark->SetWidth(4);
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// Create the regression line
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$lplot = new LinePlot($datay);
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$lplot->SetWeight(2);
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$lplot->SetColor('navy');
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// Add the pltos to the line
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$graph->Add($sp1);
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$graph->Add($lplot);
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// ... and stroke
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$graph->Stroke();
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?>
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