I took the example turning-series.html from FLOT website and made some changes. Copy and paste the following into a new HTML file and run it - works in Firefox, not tested in IE.
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>Flot Examples</title>
<link href="http://people.iola.dk/olau/flot/examples/layout.css" rel="stylesheet" type="text/css"></link>
<!--[if IE]><script language="javascript" type="text/javascript" src="http://people.iola.dk/olau/flot/excanvas.pack.js"></script><![endif]-->
<script language="javascript" type="text/javascript" src="http://people.iola.dk/olau/flot/jquery.js"></script>
<script language="javascript" type="text/javascript" src="http://people.iola.dk/olau/flot/jquery.flot.js"></script>
<style> #tooltip { font-size:8pt; } </style>
</head>
<body>
<h1>Flot Examples</h1>
<div id="placeholder" style="width:600px;height:300px;"></div>
<p>Here is an example with real data: military budgets for
various countries in constant (2005) million US dollars (source: <a href="http://www.sipri.org/">SIPRI</a>).</p>
<script id="source" language="javascript" type="text/javascript">
$(function () {
var datasets = {
"usa": {
label: "USA",
data: [[1988, 483994], [1989, 479060], [1990, 457648], [1991, 401949], [1992, 424705], [1993, 402375], [1994, 377867], [1995, 357382], [1996, 337946], [1997, 336185], [1998, 328611], [1999, 329421], [2000, 342172], [2001, 344932], [2002, 387303], [2003, 440813], [2004, 480451], [2005, 504638], [2006, 528692]]
},
"russia": {
label: "Russia",
data: [[1988, 218000], [1989, 203000], [1990, 171000], [1992, 42500], [1993, 37600], [1994, 36600], [1995, 21700], [1996, 19200], [1997, 21300], [1998, 13600], [1999, 14000], [2000, 19100], [2001, 21300], [2002, 23600], [2003, 25100], [2004, 26100], [2005, 31100], [2006, 34700]]
},
"uk": {
label: "UK",
data: [[1988, 62982], [1989, 62027], [1990, 60696], [1991, 62348], [1992, 58560], [1993, 56393], [1994, 54579], [1995, 50818], [1996, 50554], [1997, 48276], [1998, 47691], [1999, 47529], [2000, 47778], [2001, 48760], [2002, 50949], [2003, 57452], [2004, 60234], [2005, 60076], [2006, 59213]]
},
"germany": {
label: "Germany",
data: [[1988, 55627], [1989, 55475], [1990, 58464], [1991, 55134], [1992, 52436], [1993, 47139], [1994, 43962], [1995, 43238], [1996, 42395], [1997, 40854], [1998, 40993], [1999, 41822], [2000, 41147], [2001, 40474], [2002, 40604], [2003, 40044], [2004, 38816], [2005, 38060], [2006, 36984]]
},
};
// define an empty array
var data = [];
// use this existing loop...
var i = 0;
$.each(datasets, function(key, val) {
val.color = i;
++i;
// ... and add this line - so the data array is populated (row by row)
data.push(datasets[key]);
});
// plot the graph with the newly populated data array
$.plot($("#placeholder"), data, {
yaxis: { min: 0 },
xaxis: { tickDecimals: 0 },
grid: { hoverable: true, clickable: true },
points: { show: true },
lines: { show: true },
});
// add some hovering logic to each point...
var previousPoint = null;
$("#placeholder").bind("plothover", function (event, pos, item) {
$("#x").text(pos.x.toFixed(2));
$("#y").text(pos.y.toFixed(2));
if (item) {
if (previousPoint != item.datapoint) {
previousPoint = item.datapoint;
$("#tooltip").remove();
var x = item.datapoint[0].toFixed(2), y = item.datapoint[1].toFixed(2);
showTooltip(item.pageX, item.pageY, item.series.label + " of " + x + " = " + y);
}
}
else {
$("#tooltip").remove();
previousPoint = null;
}
});
// show the tooltip
function showTooltip(x, y, contents) {
$('<div id="tooltip">' + contents + '</div>').css( {
position: 'absolute',
display: 'none',
top: y - 35,
left: x + 5,
border: '1px solid #fdd',
padding: '2px',
'background-color': '#fee',
opacity: 0.80
}).appendTo("body").fadeIn(200);
}
});
</script>
</body>
</html>