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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
 <head>
    <meta http-equiv="Content-Type" content="text/html; charset=utf-8">
    <title>Flot Examples</title>
    <link href="layout.css" rel="stylesheet" type="text/css">
    <!--[if lte IE 8]><script language="javascript" type="text/javascript" src="../excanvas.min.js"></script><![endif]-->
    <script language="javascript" type="text/javascript" src="../jquery.js"></script>
    <script language="javascript" type="text/javascript" src="../jquery.flot.js"></script>
 </head>
    <body>
    <h1>Flot Examples</h1>

    <div id="placeholder" style="width:600px;height:300px;"></div>

    <p>You can update a chart periodically to get a real-time effect
    by using a timer to insert the new data in the plot and redraw it.</p>

    <p>Time between updates: <input id="updateInterval" type="text" value="" style="text-align: right; width:5em"> milliseconds</p>

<script type="text/javascript">
$(function () {
    // we use an inline data source in the example, usually data would
    // be fetched from a server
    var data = [], totalPoints = 300;
    function getRandomData() {
        if (data.length > 0)
            data = data.slice(1);

        // do a random walk
        while (data.length < totalPoints) {
            var prev = data.length > 0 ? data[data.length - 1] : 50;
            var y = prev + Math.random() * 10 - 5;
            if (y < 0)
                y = 0;
            if (y > 100)
                y = 100;
            data.push(y);
        }

        // zip the generated y values with the x values
        var res = [];
        for (var i = 0; i < data.length; ++i)
            res.push([i, data[i]])
        return res;
    }

    // setup control widget
    var updateInterval = 30;
    $("#updateInterval").val(updateInterval).change(function () {
        var v = $(this).val();
        if (v && !isNaN(+v)) {
            updateInterval = +v;
            if (updateInterval < 1)
                updateInterval = 1;
            if (updateInterval > 2000)
                updateInterval = 2000;
            $(this).val("" + updateInterval);
        }
    });

    // setup plot
    var options = {
        series: { shadowSize: 0 }, // drawing is faster without shadows
        yaxis: { min: 0, max: 100 },
        xaxis: { show: false }
    };
    var plot = $.plot($("#placeholder"), [ getRandomData() ], options);

    function update() {
        plot.setData([ getRandomData() ]);
        // since the axes don't change, we don't need to call plot.setupGrid()
        plot.draw();
        
        setTimeout(update, updateInterval);
    }

    update();
});
</script>

 </body>
</html>