图标二次绘制，折线扭曲echarts 配置项内容和展示

详细描述见代码备注，具体问题是： 绘制这小图以后，再次使用新的数据绘制图表，倒数20之前的数据出现扭曲现象

      option = {
	title:{},
	backgroundColor: '#fafbfc',
	tooltip: {
		trigger: 'axis'
	},
	legend: {
		data: [],
		top: '10%',
		left: '10%',
	},
	grid: {
		left: '10%',
		right: '4%',
		bottom: '13%',
		top: '20%',
		containLabel: true
	},
	toolbox: {
		feature: {
			/*saveAsImage: {}*/
		}
	},
	xAxis: {
		type: 'category',
		boundaryGap: false,
		data: [],
		axisLine: {
			lineStyle: {
				color: '#888'
			}
		},
		axisLabel: {
			interval: 0,
			rotate: 40,
			fontSize:12,
		}
	},
	yAxis: {
		type: 'value',
		minInterval: 1,
		boundaryGap: [0,0.1],
		axisLine: {
			lineStyle: {
				color: '#888'
			}
		}
	},
	dataZoom: [
	{
		show: true,
		start: 50,
		end: 100,
		bottom : 18
	},
	{
		type: 'inside',
		start: 50,
		end: 100
	},
	],
	series: []
}
/*要用到的数据，index0是第一次，1是2秒后第二次绘制*/
xAxis=[
["16:15:00","16:15:03","16:15:06","16:15:09","16:15:12","16:15:15","16:15:18","16:15:21","16:15:24","16:15:27","16:15:30","16:15:33","16:15:36","16:15:39","16:15:42","16:15:45","16:15:48","16:15:51","16:15:54","16:15:57","16:16:00","16:16:03","16:16:06","16:16:09","16:16:12","16:16:15","16:16:18","16:16:21","16:16:24","16:16:27","16:16:30","16:16:33","16:16:36","16:16:39","16:16:42","16:16:45","16:16:48","16:16:51","16:16:54","16:16:57","16:17:00","16:17:03","16:17:06","16:17:09","16:17:12","16:17:15","16:17:18","16:17:21","16:17:24","16:17:27"],
["16:15:30","16:15:33","16:15:36","16:15:39","16:15:42","16:15:45","16:15:48","16:15:51","16:15:54","16:15:57","16:16:00","16:16:03","16:16:06","16:16:09","16:16:12","16:16:15","16:16:18","16:16:21","16:16:24","16:16:27","16:16:30","16:16:33","16:16:36","16:16:39","16:16:42","16:16:45","16:16:48","16:16:51","16:16:54","16:16:57","16:17:00","16:17:03","16:17:06","16:17:09","16:17:12","16:17:15","16:17:18","16:17:21","16:17:24","16:17:27","16:17:30","16:17:33","16:17:36","16:17:39","16:17:42","16:17:45","16:17:48","16:17:51","16:17:54","16:17:57"]

]


legend=[
	["oms"],["oms"]
]
series=[
[{"name":"oms","type":"line","data":[41,40,40,41,40,41,41,40,41,41,40,41,41,38,41,39,39,40,39,39,40,40,38,40,40,40,39,39,39,39,41,39,39,41,39,39,39,39,38,40,39,40,39,39,40,37,39,40,38,140],"smooth":true}]
,
[{"name":"oms","type":"line","data":[40,41,41,38,41,39,39,40,39,39,40,40,38,40,40,40,39,39,39,169,41,309,39,41,39,39,39,39,38,190,39,60,39,109,40,37,39,40,38,60,40,39,39,40,40,39,39,39,40,40],"smooth":true}]
]
/*两秒钟后重新绘制，折线扭曲*/
setTimeout(function (){
    myChart.clear()
	option.xAxis.data=xAxis[1]
	option.legend.data=legend[1]
	option.series=series[1]
	myChart.setOption(option);
	console.log(option.series[0])
}, 2000);

/*赋值后绘制*/
option.xAxis.data=xAxis[0]
option.legend.data=legend[0]
option.series=series[0]
myChart.setOption(option)
console.log(option.series[0])