某个问题echarts 平均值配置项内容和展示

      option = {
    "color": "#38f",
    "grid": {
        "left": 65,
        "right": 35,
        "top": 30,
        "bottom": 55
    },
    "xAxis": {
        "type": "time",
        "min": "dataMin",
        "max": "dataMax",
        "axisLine": {
            "show": false
        },
        "axisTick": {
            "show": false
        },
        "axisLabel": {
            "margin": 15,
            "color": "#999",
            "fontSize": 12
        },
        "splitLine": {
            "show": false
        },
        "splitNumber": 15
    },
    "yAxis": {
        "type": "value",
        "axisLine": {
            "show": false
        },
        "axisTick": {
            "show": false
        },
        "axisLabel": {
            "margin": 20,
            "color": "#999",
            "fontSize": 12
        },
        "splitLine": {
            "lineStyle": {
                "color": "#f5f5f5",
                "type": "dashed"
            }
        }
    },
    "tooltip": {
        "trigger": "axis",
        "axisPointer": {
            "show": true,
            "label": {
                "show": false
            },
            "lineStyle": {
                "width": 0
            }
        },
        "backgroundColor": "#38f",
        "paddingLeft": 10,
        "paddingRight": 10,
        "textStyle": {
            "fontSize": 12
        }
    },
    "series": {
        "type": "line",
        "smooth": true,
        "symbol": "circle",
        "symbolSize": 2,
        "showSymbol": false,
        "lineStyle": {
            "width": 1
        },
        markLine: {
            precision: 8,
            data: [{
                name: '平均值',
                type: 'average'
            }],
            lineStyle: {
                color: '#000',
                type: 'dashed'
            }
        },
        "data": [
            ["2018/07/17", 0.011341],
            ["2018/07/16", 0.0111655],
            ["2018/07/15", 0.0114126],
            ["2018/07/14", 0.011566],
            ["2018/07/13", 0.0114261],
            ["2018/07/12", 0.0112994],
            ["2018/07/11", 0.0115931],
            ["2018/07/10", 0.0115528],
            ["2018/07/09", 0.0116438],
            ["2018/07/08", 0.011719],
            ["2018/07/07", 0.0114817],
            ["2018/07/06", 0.0115221],
            ["2018/07/05", 0.0115684],
            ["2018/07/04", 0.0116965],
            ["2018/07/03", 0.0116036],
            ["2018/07/02", 0.011386],
            ["2018/07/01", 0.0113893],
            ["2018/06/30", 0.011495],
            ["2018/06/29", 0.0113199],
            ["2018/06/28", 0.0107178],
            ["2018/06/27", 0.0104945],
            ["2018/06/26", 0.0102861],
            ["2018/06/25", 0.0101068],
            ["2018/06/24", 0.010452],
            ["2018/06/23", 0.0106669],
            ["2018/06/22", 0.0113784],
            ["2018/06/21", 0.0106694],
            ["2018/06/20", 0.00962346],
            ["2018/06/19", 0.00953891],
            ["2018/06/18", 0.00948168]
        ]
    }
}