function formatTooltipAsHours(value, ratio, id, index)
{
	return value.toFixed(2) + ' h';
}

function formatQuarter(d)
{
	if (d instanceof Date)
	{
		var q = d.getMonth();
		q = parseInt(q / 3) + 1;
		return 'Q' + q;
	}
	return '';
}

function formatHalfyear(d)
{
	if (d instanceof Date)
	{
		var q = d.getMonth();
		q = parseInt(q / 6) + 1;
		return 'H' + q;
	}
	return '';
}

var c3arg = {
    onrendered: updateFrameHeight,
	data: chartData,
	grid: {
		y: {
			show: true
		},
		x: {
			show: true
		}
	},
	axis: {
		x: {
			type: 'timeseries',
			label: {
				text: chartData.custom.xLabel,
				position: 'outer-left'
			},
			tick: {
				format: eval(chartData.custom.xTickFormat),
				culling: {
					max: 25
				},
				fit: true,
				multiline: false
			}
		},
		y: {
			label: chartData.ytype
		}
	}
};

if (chartData.custom && chartData.custom.tooltip)
{
	var tooltipFunction = eval(chartData.custom.tooltip);
	c3arg.tooltip = {
		format: {
			value: tooltipFunction
		}
	};
}

if ( chartData.custom && chartData.custom.gauge_max)
{
	c3arg.gauge = {
		max: parseFloat(chartData.custom.gauge_max)
	};
}

c3.generate(c3arg);