Max and min value in line graph nor drawn properly

[smitaag]

I am making a line graph using below details, but the max and min points are not plotted as part of the graph but are being plotted as different points.

var chart;var minValue;var maxValue;chart = new dojox.charting.Chart('defaultPCMchart782824634Id',{ margins: {l: 0,r: 0, t: 0, b: 0}});chart.addAxis('x', {includeZero:false,leftBottom:true,vertical:false,type:'Invisible',fixUpper:'major',fixLower:'major',stroke: {color:'#000000',width :2},labelFunc : function(timeInMilliSeconds){var date=calcLocalTime(timeInMilliSeconds,0.0);var formattedDate=dojo.date.locale.format(date,{locale:'en-us'});return formattedDate;}});chart.addAxis('y', {includeZero:true,leftBottom:true,vertical:true,type:'Invisible',fixUpper:'major',fixLower:'major',stroke: {color:'#000000',width :2},labelFunc: formatAxisLabel});chart.addPlot('procUtilTrendSparkLineByLpar', {type: 'Lines',tension:5, markers:true,hAxis: 'x',vAxis: 'y',styleFunc: function(item) {if(item.y == maxValue){return {stroke: {color:'#F04E37', width:2}, fill: '#F04E37' };}else if(item.y == minValue){return {stroke: {color:'#FFE34F', width:2}, fill: '#FFE34F' };}else {return {stroke: {color:'#EDEDED', width:1}, fill: '#4682b3' };}}});chart.addSeries('procUtilServerUsageTrafficLine',[{x:1436263200000.000,y:0.002,tooltip:null},{x:1436270400000.000,y:0.003,tooltip:null},{x:1436277600000.000,y:0.002,tooltip:null},{x:1436284800000.000,y:0.003,tooltip:null},{x:1436292000000.000,y:0.003,tooltip:null},{x:1436299200000.000,y:0.003,tooltip:null},{x:1436306400000.000,y:0.009,tooltip:null},{x:1436313600000.000,y:0.002,tooltip:null},{x:1436320800000.000,y:0.002,tooltip:null},{x:1436328000000.000,y:0.002,tooltip:null},{x:1436335200000.000,y:0.003,tooltip:null},{x:1436342400000.000,y:0.003,tooltip:null},{x:1436349600000.000,y:0.003,tooltip:null},{x:1436356800000.000,y:0.003,tooltip:null},{x:1436364000000.000,y:null,tooltip:null},{x:1436371200000.000,y:null,tooltip:null},{x:1436378400000.000,y:null,tooltip:null},{x:1436385600000.000,y:null,tooltip:null},{x:1436392800000.000,y:null,tooltip:n

[smitaag]

screenshot of the issue