ECharts Y坐标添加min 和max之后间距不一echarts 折线配置项内容和展示

1、需求是类似股票实时走向图（如：https://gupiao.baidu.com/stock/sh000001.html?from=aladingpc） 2、不知道用K图还是折线图？ 用K图的话不用图上股票那些长方形，要添加折线走向怎么弄？ 用折线图的话，坐标原点不为0，而且实时更新，要怎么弄？ 3、图上是用折线图，设置y坐标的min 和 max。。但是会出现y坐标的间距大小不一的情况。。 求大神破哇~~

      // 基于准备好的dom，初始化echarts实例
      

        // 指定图表的配置项和数据
        var option = {
            title: {
                text: 'ECharts 入门示例'
            },
            tooltip: {},
         
            legend: {
                data:['销量']
            },
            xAxis: {
                type: 'category',
                scale: true,
                boundaryGap : false,
                data: ["2016/6/01","2016/6/02","2016/6/03","2016/6/04","2016/6/05","2016/6/06","2016/6/07","2016/6/08","2016/6/09","2016/6/10","2016/6/11","2016/6/12","2016/6/13","2016/6/14","2016/6/15","2016/6/16","2016/6/17","2016/6/18","2016/6/19","2016/6/20"]

            },
            yAxis: {
                type: 'value',
                scale:true,
                boundaryGap: [0.01, 0.01]
            },
         
            series: [{
                name: '销量',
                type: 'line',
                data: [575, 257, 336, 330, 295, 379,367,390,334,271,314,333,273,286,247,290,341,366,336,291,400],
                itemStyle : {
                    normal : {
                        lineStyle:{
                            color:'#fe7c2e'
                        }
                    }
                },
                areaStyle: {
                    normal: {
                        color: '#fff4ee'
                    }
                }
            }]
        };