echarts多条折线图动态分层

var xData = param.xData;

    var data = param.yData    let option = [];    let num =param.num ? param.num : 0;    let max = num ? num *100 : 100;    //处理精度丢失问题  但不是最佳方案

option = {

        title: {            left: 'center',            text: param.title        },        tooltip: {            trigger: 'axis',        },        legend: {            right:0,            data:param.tName,        },        grid: {            left: '3%',            right: '4%',            bottom: '3%',            containLabel: true        },        xAxis: {            boundaryGap: false,            data:param.xData        },        yAxis: {            name: param.yName,            splitLine: { show: false },                    },        series: []    }    option[6].series.push(        {            name: '平行于y轴的趋势线',            type: 'line',            //data:[0],            markLine: {                silent: true,                data: [{                    yAxis: num                }]            }        }    )    if( param.option_type == 6){        for( var item in param.yData){            var obj ={                name: param.yData[item].name,                type: 'line',                color:param.yData[item].color,                data: param.yData[item].data            }            option[6].series.push(obj)        }    }