[Saurabh singh]

yes it was very help full for string comparison you can you below code.

function displayGraph(graphData){
var chart = new CanvasJS.Chart("chartContainer1",graphData);
	chart.options.data.forEach(function(element) {
    element.dataPoints.sort(compareDataPoint);
	});
	chart.render();
}

function compareDataPoint(dataPoint1, dataPoint2) {
// instead of label you can also use dataPoint.x  or dataPoint.y depends on you requirment
	if (dataPoint1.label < dataPoint2.label){return -1}
	if ( dataPoint1.label > dataPoint2.label){return 1}
	return 0
}