src/chart/baseGroupedStackTimeBarChart.js
function drawSelection(dataArray) {
		var firstItem = (dataArray && dataArray.length > 0 ? dataArray.slice(0, 1) : []),
			firstItemX = (dataArray && dataArray.length > 0 ? valueX(dataArray[0]) : 0),
			lastItemX = (dataArray && dataArray.length > 0 ? valueX(dataArray[dataArray.length - 1]) : 0),
			width = (lastItemX - firstItemX) + xBar.rangeBand();
		var selectBar = parent.svgHoverRoot.selectAll('rect.selectionbar').data(firstItem);
		selectBar.attr('x', firstItemX)
				.attr('width', width);
		selectBar.enter().append('rect')
				.attr('x', firstItemX)
				.attr('y', 0)
				.attr('height', parent.height)
				.attr('width', width)
				.classed('selectionbar clickable', true);
		selectBar.exit().remove();
	}
function drawSelection(dataArray) {
		var firstItem = (dataArray && dataArray.length > 0 ? dataArray.slice(0, 1) : []),
			firstItemX = (dataArray && dataArray.length > 0 ? valueX(dataArray[0]) : 0),
			lastItemX = (dataArray && dataArray.length > 0 ? valueX(dataArray[dataArray.length - 1]) : 0),
			width = (lastItemX - firstItemX) + xBar.rangeBand();
		var selectBar = parent.svgHoverRoot.selectAll('rect.selectionbar').data(firstItem);
		selectBar.attr('x', firstItemX)
				.attr('width', width);
		selectBar.enter().append('rect')
				.attr('x', firstItemX)
				.attr('y', 0)
				.attr('height', parent.height)
				.attr('width', width)
				.classed('selectionbar clickable', true);
		selectBar.exit().remove();
	}
function drawSelection ( dataArray ) { var firstItem = ( dataArray && dataArray . length > 0 ? dataArray . slice ( 0 , 1 ) : [ ] ) , firstItemX = ( dataArray && dataArray . length > 0 ? valueX ( dataArray [ 0 ] ) : 0 ) , lastItemX = ( dataArray && dataArray . length > 0 ? valueX ( dataArray [ dataArray . length - 1 ] ) : 0 ) , width = ( lastItemX - firstItemX ) + xBar . rangeBand ( ) ; var selectBar = parent . svgHoverRoot . selectAll ( 'rect.selectionbar' ) . data ( firstItem ) ; selectBar . attr ( 'x' , firstItemX ) . attr ( 'width' , width ) ; selectBar . enter ( ) . append ( 'rect' ) . attr ( 'x' , firstItemX ) . attr ( 'y' , 0 ) . attr ( 'height' , parent . height ) . attr ( 'width' , width ) . classed ( 'selectionbar clickable' , true ) ; selectBar . exit ( ) . remove ( ) ; }
Render a "selection" rect over a set of bars.

@param {array} dataArray An array of data elements for which to render a selection over.
Pass an empty array to remove the selection.
Render a selection rect over a set of bars .