echarts鼠标移上去显示数据

<script src="/assets/webmaster/js/jquery.min.js"></script> <script src="/assets/webmaster/js/echarts.min.js"></script> <script type="text/javascript">     // 基于准备好的dom，初始化echarts实例     var myChart = echarts.init(document.getElementById('latest_pv'));      // 指定图表的配置项和数据     var option = {         xAxis: {             type: 'category',             data: ['{$d1}', '{$d2}', '{$d3}', '{$d4}', '{$d5}', '{$d6}', '{$d7}']         },         yAxis: {             type: 'value'         },         series: [{             data: [{$uv1}, {$uv2}, {$uv3}, {$uv4}, {$uv5}, {$uv6}, {$uv7}],             type: 'line'         }],         tooltip : {             trigger: 'axis',             axisPointer: {                 type: 'cross',                 label: {                     backgroundColor: '#6a7985'                 }             }         }         };      // 使用刚指定的配置项和数据显示图表。     myChart.setOption(option); </script>