source: trunk/xgraph/jpgraph/Examples/windrose_ex7.php

<?php
require_once ('jpgraph/jpgraph.php');
require_once ('jpgraph/jpgraph_windrose.php');

$data = array(
    2 => array(1,15,7.5,2),
    5 => array(1,1,1.5,2),
    7 => array(1,2,10,3,2),
    9 => array(2,3,1,3,1,2),
    );

// First create a new windrose graph with a title
$graph = new WindroseGraph(400,450);
$graph->title->Set('Windrose example 7');
$graph->title->SetFont(FF_VERDANA,FS_BOLD,14);
$graph->title->SetColor('navy');

// Create the free windrose plot.
$wp = new WindrosePlot($data);
$wp->SetType(WINDROSE_TYPE16);

// Add some "arbitrary" text to the center
$wp->scale->SetZeroLabel("SOx\n8%%");

// Localize the compass direction labels into Swedish
// Note: The labels for data must now also match the exact
// string for the compass directions.
$se_CompassLbl = array('O','ONO','NO','NNO','N','NNV','NV','VNV',
                                   'V','VSV','SV','SSV','S','SSO','SO','OSO');
$wp->SetCompassLabels($se_CompassLbl);

// Localize the "Calm" text into Swedish and make the circle
// slightly bigger than default
$se_calmtext = 'Lugnt';
$wp->legend->SetCircleText($se_calmtext);
$wp->legend->SetCircleRadius(20);

// Adjust the displayed ranges
$ranges = array(1,3,5,8,12,19,29);
$wp->SetRanges($ranges);
//$wp->SetAntiAlias(true);

// Set the scale to always have max value of 30 with a step
// size of 12.
$wp->scale->Set(30,12);

// Finally add it to the graph and send back to client
$graph->Add($wp);
$graph->Stroke();
?>