Graph图表，即使数据为空

Question

我正在使用列表创建图形：

list: [[7, 8, 9, 6, 5], [8, 8.8, 7.9, 9, 5]]

例如：长度为2的列表，并且列表是动态生成的，长度可以为2或更大。

以及如何使用动态列表绘制图形。

var ctx = document.getElementById('radar-chart');
var arr = {{ rating }};
var lab = '{{ brand_name }}';
console.log(lab);
Chart.defaults.global.defaultFontColor = '#000';
new Chart(ctx, {
type: 'radar',
data: {
  labels: ["Design", "Performance", "Camera", "Connectivity", "Battery"],
  datasets: [
    {
      label: "{{ brand_name.0 }}",
      fill: true,
      backgroundColor: "rgba(179,181,198,0.2)",
      borderColor: "rgba(179,181,198,1)",
      pointBorderColor: "#fff",
      pointBackgroundColor: "rgba(179,181,198,1)",
      data: list[0]
    }, {
      label: "{{ brand_name.1 }}",
      fill: true,
      backgroundColor: "rgba(255,99,132,0.2)",
      borderColor: "rgba(255,99,132,1)",
      pointBorderColor: "#fff",
      pointBackgroundColor: "rgba(255,99,132,1)",
      pointBorderColor: "#fff",
      data:  list[1]
    },

  ]
},
options: {
    responsive: true,
maintainAspectRatio: false,
    responsiveAnimationDuration: 1

},

legend:
    {
        labels:{
            color: '#000'
        }

    },
layout:{
    height: 200,
    padding:{
        left: 50,
        right: 0,
        bottom: 0,
        top: 0
    }
}
});