对比、价差与比值

import { Chart } from '@tradecanvas/chart'

const chart = new Chart(el, { theme: 'dark' })
chart.setData(bars)
// Other symbols on the same chart: id, label, their bars, a colour
chart.addCompareSymbol('MSFT', 'MSFT', msftBars, '#3b82f6')
chart.addCompareSymbol('NVDA', 'NVDA', nvdaBars, '#22c55e')
chart.setCompareMode('percent')     // or 'absolute'

// As new bars arrive
chart.updateCompareData('MSFT', msftBars)