source: trunk/xgraph/jpgraph/Examples/contourex04.php

<?php // content="text/plain; charset=utf-8"
// Contour plot example 04

require_once ('jpgraph/jpgraph.php');
require_once ('jpgraph/jpgraph_contour.php');

$data = array(
    array (12,12,10,10,8,4),
    array (10,10,8,14,10,3),
    array (7,7,13,17,12,8),
    array (4,5,8,12,7,6),
    array (10,8,7,8,10,4));

// Setup a basic graph context with some generous margins to be able
// to fit the legend
$graph = new Graph(500,380);
$graph->SetMargin(40,140,60,40);

$graph->title->Set("Example of interpolated contour plot");
$graph->title->SetFont(FF_ARIAL,FS_BOLD,14);
$graph->title->SetMargin(10);

// For contour plots it is custom to use a box style ofr the axis
$graph->legend->SetPos(0.05,0.5,'right','center');
$graph->SetScale('intint');

// Setup axis and grids
$graph->SetAxisStyle(AXSTYLE_BOXOUT);
$graph->xgrid->SetLineStyle('dashed');
$graph->xgrid->Show(true);
$graph->ygrid->SetLineStyle('dashed');
$graph->ygrid->Show(true);

// A simple contour plot with 10 isobar lines and flipped Y-coordinates
// Make the data smoother by interpolate the original matrice by a factor of two
// which will make each grid cell half the original size
$cp = new ContourPlot($data,10, 2);

$cp->UseHighContrastColor(true);

// Display the legend
$cp->ShowLegend();

// Make the isobar lines slightly thicker
$graph->Add($cp);

// ... and send the graph back to the browser
$graph->Stroke();

?>