client/splunk.ui.charting.js
function defaultFormatter() {
			var pThis = this,
				items = pThis.points || splat(pThis),
				xAxis = items[0].series.xAxis,
				x = pThis.x,
				isDateTime = xAxis && xAxis.options.type === 'datetime',
				useHeader = isString(x) || isDateTime,
				s;

			// build the header
			s = useHeader ?
				['<span style="font-size: 10px">' +
				(isDateTime ? dateFormat('%A, %b %e, %Y', x) :  x) +
				'</span>'] : [];

			// build the values
			each(items, function (item) {
				s.push(item.point.tooltipFormatter(useHeader));
			});
			return s.join('<br/>');
		}
function defaultFormatter() {
			var pThis = this,
				items = pThis.points || splat(pThis),
				xAxis = items[0].series.xAxis,
				x = pThis.x,
				isDateTime = xAxis && xAxis.options.type === 'datetime',
				useHeader = isString(x) || isDateTime,
				s;

			// build the header
			s = useHeader ?
				['<span style="font-size: 10px">' +
				(isDateTime ? dateFormat('%A, %b %e, %Y', x) :  x) +
				'</span>'] : [];

			// build the values
			each(items, function (item) {
				s.push(item.point.tooltipFormatter(useHeader));
			});
			return s.join('<br/>');
		}
function defaultFormatter ( ) { var pThis = this , items = pThis . points || splat ( pThis ) , xAxis = items [ 0 ] . series . xAxis , x = pThis . x , isDateTime = xAxis && xAxis . options . type === 'datetime' , useHeader = isString ( x ) || isDateTime , s ; // build the header
 s = useHeader ? [ '<span style="font-size: 10px">' + ( isDateTime ? dateFormat ( '%A, %b %e, %Y' , x ) : x ) + '</span>' ] : [ ] ; // build the values
 each ( items , function ( item ) { s . push ( item . point . tooltipFormatter ( useHeader ) ) ; } ) ; return s . join ( '<br/>' ) ; }
In case no user defined formatter is given, this will be used
In case no user defined formatter is given this will be used