BarChart

A vertical bar chart with Y-axis labels and X-axis labels.

Constructor

new BarChart(data: ChartData, options?: BarChartOptions)

ChartData

interface ChartData {
  labels: string[]
  values: number[]
}

BarChartOptions

Property	Type	Default	Description
fill	boolean	false	Fill bars without gaps (area chart look)

Methods

render()

render(width: number, height: number): CharGrid

Renders a bar chart with:

• Y-axis with tick marks (up to 5 ticks)
• Bars using \u2588 (full block) character
• X-axis labels (date labels YYYY-MM-DD auto-shortened to MM/DD)
• Auto-scaled to max value

setData()

setData(data: ChartData): void

Replace the chart data. Call app.update() afterward.

Examples

// basic chart
new BarChart({
  labels: ['Mon', 'Tue', 'Wed', 'Thu', 'Fri'],
  values: [10, 25, 15, 30, 20],
})

// filled (no gaps between bars)
new BarChart(data, { fill: true })

// inside a box
new Box('Revenue', new BarChart(data))

// live-updating chart
const chart = new BarChart(data)
setInterval(() => {
  data.values.push(Math.random() * 100)
  data.labels.push(String(data.values.length))
  if (data.values.length > 30) {
    data.values.shift()
    data.labels.shift()
  }
  chart.setData(data)
  app.update()
}, 500)