A basic example of the drawing API marker1 object

[No canvas support]

This goes in the documents header:
<script src="RGraph.common.core.js"></script>
<script src="RGraph.common.tooltips.js"></script>
<script src="RGraph.common.dynamic.js"></script>
<script src="RGraph.drawing.marker1.js"></script>
<script src="RGraph.line.js"></script>
Put this where you want the chart to show up:
<canvas id="cvs" width="600" height="250">
    [No canvas support]
</canvas>
This is the code that generates the chart:
<script>
    line = new RGraph.Line({
        id: 'cvs',
        data: [5,8,6,4,3,5,2],
        options: {
            hmargin: 5,
            xaxisLabels: ['Monday','Tuesday','Wednesday','Thursday','Friday','Saturday','Sunday']
        }
    }).draw();

    marker1 = new RGraph.Drawing.Marker1({
        id: 'cvs',
        x: ((550 / 6) * 4) + 25,
        y: line.coords[4][1],
        radius: 35,
        text: 'Woohoo!',
        options: {
            tooltips: ['Lou'],
            tooltipsNohideonclear: true,
            align: 'left'
        }
    }).draw();
</script>