jqplot条形图日期类别格式化xaxis

Question

axes: { 
    renderer: $.jqplot.CategoryAxisRenderer,
    label: 'Date',
    ticks: myTicks,
    labelRenderer: $.jqplot.CanvasAxisLabelRenderer,
    tickRenderer: $.jqplot.CanvasAxisTickRenderer,
    tickOptions: {
        angle: -30}
    }
}

My Result

我需要一个普通的格式化xaxis，比如this