AgentSkillsCN

chartjs-chart-types

当用户询问“如何创建折线图”“Chart.js 条形图”“Chart.js 饼图”“甜甜圈图”“雷达图”“极坐标面积图”“气泡图”“散点图”“混合图表”“组合图表”“面积图”“堆叠图”“横向条形图”“Chart.js 图表类型”“数据集属性”“图表数据结构”,或在实现 Chart.js v4.5.1 特定图表类型时遇到困难时,可使用此技能。

SKILL.md
--- frontmatter
name: chartjs-chart-types
description: This skill should be used when the user asks "how to create a line chart", "Chart.js bar chart", "pie chart Chart.js", "doughnut chart", "radar chart", "polar area chart", "bubble chart", "scatter chart", "mixed chart", "combo chart", "area chart", "stacked chart", "horizontal bar chart", "Chart.js chart types", "dataset properties", "chart data structure", or needs help implementing specific Chart.js v4.5.1 chart types.

Chart.js Chart Types (v4.5.1)

Complete guide to all Chart.js chart types, their configuration, and dataset properties.

Available Chart Types

TypeDescriptionUse Case
lineLine chartTrends over time
barBar chartComparing categories
piePie chartParts of a whole
doughnutDoughnut chartParts of a whole with center
radarRadar/spider chartMultivariate data comparison
polarAreaPolar area chartCyclical data
bubbleBubble chartThree dimensions
scatterScatter plotCorrelation analysis

Line Chart

Show trends and changes over time:

javascript
new Chart(ctx, {
  type: 'line',
  data: {
    labels: ['Jan', 'Feb', 'Mar', 'Apr', 'May'],
    datasets: [{
      label: 'Sales',
      data: [65, 59, 80, 81, 56],
      fill: false,
      borderColor: 'rgb(75, 192, 192)',
      tension: 0.1  // 0 = straight lines, 0.4 = curved
    }]
  }
});

Key Line Properties

PropertyTypeDescription
tensionnumberBezier curve tension (0-1)
fillboolean/stringFill area under line
steppedboolean/stringStepped line interpolation
borderDashnumber[]Dashed line pattern
pointRadiusnumberData point size
pointStylestringPoint shape (circle, rect, triangle, etc.)
spanGapsbooleanConnect over null values

Vertical Line Chart

Flip axes with indexAxis:

javascript
options: {
  indexAxis: 'y'  // Vertical line chart
}

Bar Chart

Compare discrete categories:

javascript
new Chart(ctx, {
  type: 'bar',
  data: {
    labels: ['Red', 'Blue', 'Yellow', 'Green'],
    datasets: [{
      label: 'Votes',
      data: [12, 19, 3, 5],
      backgroundColor: [
        'rgba(255, 99, 132, 0.5)',
        'rgba(54, 162, 235, 0.5)',
        'rgba(255, 206, 86, 0.5)',
        'rgba(75, 192, 192, 0.5)'
      ],
      borderWidth: 1
    }]
  },
  options: {
    scales: {
      y: { beginAtZero: true }
    }
  }
});

Key Bar Properties

PropertyTypeDescription
barThicknessnumber/'flex'Bar width in pixels
barPercentagenumberBar width relative to category (0-1)
categoryPercentagenumberCategory width (0-1)
borderRadiusnumber/objectRounded corners
borderSkippedstringWhich border to skip

Horizontal Bar Chart

javascript
options: {
  indexAxis: 'y'  // Makes bars horizontal
}

Stacked Bar Chart

javascript
options: {
  scales: {
    x: { stacked: true },
    y: { stacked: true }
  }
}

Pie & Doughnut Charts

Show proportional data:

javascript
// Pie chart
new Chart(ctx, {
  type: 'pie',
  data: {
    labels: ['Red', 'Blue', 'Yellow'],
    datasets: [{
      data: [300, 50, 100],
      backgroundColor: ['#ff6384', '#36a2eb', '#ffce56']
    }]
  }
});

// Doughnut chart
new Chart(ctx, {
  type: 'doughnut',
  data: { /* same as pie */ },
  options: {
    cutout: '50%'  // Size of center hole
  }
});

Key Pie/Doughnut Properties

PropertyTypeDescription
cutoutnumber/stringCenter hole size (doughnut)
rotationnumberStarting angle (degrees)
circumferencenumberArc sweep (degrees)
offsetnumberArc offset on hover
hoverOffsetnumberOffset when hovering

Semi-Circle Chart

javascript
options: {
  rotation: -90,
  circumference: 180
}

Radar Chart

Compare multiple variables across categories:

javascript
new Chart(ctx, {
  type: 'radar',
  data: {
    labels: ['Speed', 'Power', 'Defense', 'Stamina', 'Agility'],
    datasets: [{
      label: 'Player A',
      data: [65, 59, 90, 81, 56],
      fill: true,
      backgroundColor: 'rgba(255, 99, 132, 0.2)',
      borderColor: 'rgb(255, 99, 132)',
      pointBackgroundColor: 'rgb(255, 99, 132)'
    }, {
      label: 'Player B',
      data: [28, 48, 40, 19, 96],
      fill: true,
      backgroundColor: 'rgba(54, 162, 235, 0.2)',
      borderColor: 'rgb(54, 162, 235)'
    }]
  },
  options: {
    scales: {
      r: {
        angleLines: { display: true },
        suggestedMin: 0,
        suggestedMax: 100
      }
    }
  }
});

Polar Area Chart

Like pie but with equal angles, varying radius:

javascript
new Chart(ctx, {
  type: 'polarArea',
  data: {
    labels: ['Red', 'Green', 'Yellow', 'Grey', 'Blue'],
    datasets: [{
      data: [11, 16, 7, 3, 14],
      backgroundColor: [
        'rgba(255, 99, 132, 0.5)',
        'rgba(75, 192, 192, 0.5)',
        'rgba(255, 205, 86, 0.5)',
        'rgba(201, 203, 207, 0.5)',
        'rgba(54, 162, 235, 0.5)'
      ]
    }]
  }
});

Scatter Chart

Show correlation between two variables:

javascript
new Chart(ctx, {
  type: 'scatter',
  data: {
    datasets: [{
      label: 'Data Points',
      data: [
        { x: 10, y: 20 },
        { x: 15, y: 10 },
        { x: 20, y: 30 },
        { x: 25, y: 25 }
      ],
      backgroundColor: 'rgb(255, 99, 132)'
    }]
  },
  options: {
    scales: {
      x: { type: 'linear', position: 'bottom' },
      y: { type: 'linear' }
    }
  }
});

Bubble Chart

Three-dimensional data visualization:

javascript
new Chart(ctx, {
  type: 'bubble',
  data: {
    datasets: [{
      label: 'Dataset',
      data: [
        { x: 20, y: 30, r: 15 },  // r = bubble radius
        { x: 40, y: 10, r: 10 },
        { x: 30, y: 22, r: 25 }
      ],
      backgroundColor: 'rgba(255, 99, 132, 0.5)'
    }]
  },
  options: {
    aspectRatio: 1  // Square chart for bubbles
  }
});

Area Chart

Line chart with filled area:

javascript
new Chart(ctx, {
  type: 'line',
  data: {
    labels: ['Jan', 'Feb', 'Mar', 'Apr', 'May'],
    datasets: [{
      label: 'Revenue',
      data: [65, 59, 80, 81, 56],
      fill: true,  // Enable fill
      backgroundColor: 'rgba(75, 192, 192, 0.2)',
      borderColor: 'rgb(75, 192, 192)'
    }]
  }
});

Fill Options

ValueDescription
falseNo fill (default)
trueFill to origin
'origin'Fill to origin
'start'Fill to bottom
'end'Fill to top
'-1'Fill to previous dataset
'+1'Fill to next dataset

Mixed Charts

Combine multiple chart types:

javascript
new Chart(ctx, {
  type: 'bar',  // Base type
  data: {
    labels: ['Jan', 'Feb', 'Mar', 'Apr'],
    datasets: [
      {
        type: 'line',  // Override type for this dataset
        label: 'Trend',
        data: [50, 60, 70, 80],
        borderColor: 'rgb(255, 99, 132)',
        fill: false
      },
      {
        type: 'bar',  // Explicit bar type
        label: 'Sales',
        data: [40, 55, 65, 75],
        backgroundColor: 'rgba(54, 162, 235, 0.5)'
      }
    ]
  }
});

Drawing Order

Control which dataset renders on top:

javascript
datasets: [
  { label: 'Bars', order: 2 },  // Drawn first (behind)
  { label: 'Line', order: 1 }   // Drawn last (on top)
]

Data Structures

Standard Format

javascript
data: {
  labels: ['A', 'B', 'C'],
  datasets: [{
    data: [10, 20, 30]
  }]
}

Object Format

javascript
datasets: [{
  data: [
    { x: 'A', y: 10 },
    { x: 'B', y: 20 },
    { x: 'C', y: 30 }
  ]
}]

Parsed Data Format

javascript
datasets: [{
  data: [
    { id: 'Sales', value: 100 },
    { id: 'Revenue', value: 200 }
  ],
  parsing: {
    xAxisKey: 'id',
    yAxisKey: 'value'
  }
}]

Additional Resources

  • See references/dataset-properties.md for complete property reference
  • See examples/ for working HTML examples:
    • line-area-charts.html - Line charts with tension, area fills, stepped lines
    • bar-charts.html - Vertical, horizontal, stacked bars, and mixed bar+line
    • circular-charts.html - Pie, doughnut, semi-circle gauge, polar area, radar