javascript - Chart.js 压缩条形图上的垂直轴

Question

我有一个数据集，其中最后一个值总是很高。这导致我的条形图出现问题；如果不将鼠标悬停在它们上面，几乎所有其他值都很难感受。

这是一个屏幕截图:



这就是我想要达到的目标；



所以我的问题；这在 vanilla Chart.js 中是否可行，还是我需要一个插件？如果是这样;有现成的插件还是我需要自己写一个？

我也对最初问题的替代解决方案持开放态度。

我已经在互联网上到处寻找类似的东西，但不幸的是没有太多运气。

Answer 1

您可以使用 logarithmic类型 yAxis
默认值:线性的

https://www.chartjs.org/docs/latest/axes/cartesian/logarithmic.html

var ctx = document.getElementById('myChart');

var myChart = new Chart(ctx, {
  type: 'bar',
  data: {
    labels: ["January", "February", "March", "April", "May", "June"],
    datasets: [{
      label: "Series 1",
      backgroundColor: "rgba(255,99,132,0.2)",
      borderColor: "rgba(255,99,132,1)",
      borderWidth: 2,
      hoverBackgroundColor: "rgba(255,99,132,0.4)",
      hoverBorderColor: "rgba(255,99,132,1)",
      data: [65, 59, 43, 81, 56, 950],
    }]
  },
  options: {
    scales: {
      yAxes: [{
        type: 'logarithmic',
        ticks: {
          callback: function(tick, index, ticks) {
            return tick.toLocaleString();
          }
        }
      }]
    }
  }
});

<script src="https://cdn.jsdelivr.net/npm/chart.js@2.8.0"></script>
<canvas id="myChart" width="400" height="200"></canvas>

优化报价

50 * (Math.floor(i / 50)), // lower 50
50 * (Math.ceil(i / 50)) // higer 50

var ctx = document.getElementById('myChart');

var myChart = new Chart(ctx, {
  type: 'bar',
  data: {
    labels: ["January", "February", "March", "April", "May", "June"],
    datasets: [{
      label: "Series 1",
      backgroundColor: "rgba(255,99,132,0.2)",
      borderColor: "rgba(255,99,132,1)",
      borderWidth: 2,
      hoverBackgroundColor: "rgba(255,99,132,0.4)",
      hoverBorderColor: "rgba(255,99,132,1)",
      data: [65, 59, 43, 81, 56, 950],
    }]
  },
  options: {
    scales: {
      yAxes: [{
        type: 'logarithmic',
        ticks: {
          callback: function(tick, index, ticks) {
            return tick.toLocaleString();
          }
        },
        afterBuildTicks: function(pckBarChart) {
          pckBarChart.ticks = pckBarChart.chart.data.datasets[0].data.flatMap(i => [
            50 * (Math.floor(i / 50)), // lower 50
            50 * (Math.ceil(i / 50)) // higer 50
          ])
        }
      }]
    }
  }
});

<script src="https://cdn.jsdelivr.net/npm/chart.js@2.8.0"></script>
<canvas id="myChart" width="400" height="200"></canvas>