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

<?php // content="text/plain; charset=utf-8"
require_once ('../jpgraph.php');
require_once ('../jpgraph_line.php');
require_once ('../jpgraph_date.php');

//Create some test data
$xdata = array();
$ydata = array();

// Timestamps - 2h (=7200s) apart starting 
$sampling = 7200;
$n = 50; // data points
for($i=0; $i < $n; ++$i ) {
    $xdata[$i] = time() + $i * $sampling;
    $ydata[0][$i] = rand(12,15);
    $ydata[1][$i] = rand(100,155);
    $ydata[2][$i] = rand(20,30);
}

function formatDate(&$aVal) {
    $aVal = date('Y-m-d H:i',$aVal);
}

// Apply this format to all time values in the data to prepare it to be display
array_walk($xdata,'formatDate');

// Create the graph. 
$graph  = new Graph(600, 350);
$graph->title->Set('Accumulated values with specified X-axis scale');
$graph->SetScale('textlin');

// Setup margin color
$graph->SetMarginColor('green@0.95');

// Adjust the margin to make room for the X-labels
$graph->SetMargin(40,30,40,120);

// Turn the tick marks out from the plot area
$graph->xaxis->SetTickSide(SIDE_BOTTOM);
$graph->yaxis->SetTickSide(SIDE_LEFT);

$p0 =new LinePlot($ydata[0]);
$p0->SetFillColor('sandybrown');
$p1 =new LinePlot($ydata[1]);
$p1->SetFillColor('lightblue');
$p2 =new LinePlot($ydata[2]);
$p2->SetFillColor('red');
$ap = new AccLinePlot(array($p0,$p1,$p2));

$graph->xaxis->SetTickLabels($xdata);
$graph->xaxis->SetTextLabelInterval(4);

// Add the plot to the graph
$graph->Add($ap);

// Set the angle for the labels to 90 degrees
$graph->xaxis->SetLabelAngle(90);

// Display the graph
$graph->Stroke();
?>