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javascriptchartschart.js

Small value in doughnut chart is not visible - Chartjs

Small data isn't visible for doughnut chart type. Can i resize it without change label value? display

My chart options:

options: {
    cutoutPercentage: 65,
    maintainAspectRatio: false,
    legend: {
        display: false
    },
    plugins: {
        datalabels: {
            display: false
        }
    },
    tooltips: {
        enabled: true,
        mode: 'nearest'
    },
     scales: {
        yAxes: [{
            ticks: {
                max: 5,
                min: 0,
                stepSize: 0.5
            }
        }]
    }

}

Example: http://jsfiddle.net/Lkya2tqb/

Solution

  • I converted the dataset to percent and round a small value to 1.

    var seriesData = [1,210,215];
var total = seriesData.reduce((a,v) => a + v);
var inPercent = seriesData.map(v => Math.max(v / total * 100, 1));

    Create callback for tooltip.

    tooltips: {
  callbacks: {
    label: function(tooltipItem, data) {
      var value = seriesData[tooltipItem.index];
      var label = data.labels[tooltipItem.index];
      return `${label}: ${value}`;
    }
  }


    var seriesData = [1, 210, 215];
var total = seriesData.reduce((a, v) => a + v);
var inPercent = seriesData.map(v => Math.max(v / total * 100, 1));

var labelsData = ["one", "two", "second"];
var backgroundColors = ["#FBC02D", "#E64A19", "#388E3C"]
var t = new Chart(document.getElementById('broadcast').getContext('2d'), {
  type: "doughnut",
  data: {
    datasets: [{
      data: inPercent,
      backgroundColor: backgroundColors,
      hoverBorderColor: "#fff"
    }],
    labels: labelsData,
  },
  options: {
    cutoutPercentage: 65,
    maintainAspectRatio: false,
    legend: {
      display: false
    },
    plugins: {
      datalabels: {
        display: false
      }
    },
    tooltips: {
      enabled: true,
      mode: 'nearest',
      callbacks: {
        label: function(tooltipItem, data) {
          var value = seriesData[tooltipItem.index];
          var label = labelsData[tooltipItem.index];
          return `${label}: ${value}`;
        }
      }
    }


  }
});
    <script src="https://cdn.jsdelivr.net/npm/chart.js"></script>
<canvas id="broadcast" width="350" height="250" style="width: 350px; height: 250px;"></canvas>