SolutionThere is a chart instance already initialized on the dom warning

  echarts console warning does not affect use, but affects the look and feel. The clearing method is as follows:

//存在Dom节点：获取已有的echarts实例的Dom节点
var averageChart = echarts.getInstanceByDom(document.getElementById('average-chart'))
//不存在：进行初始化
if (averageChart == null) {
    averageChart = echarts.init(document.getElementById('average-chart'))
    }