--- title: useChart description: Provides utilities to manage and format data for charts --- The `useChart` hook provides a set of utilities to manage and format data for charts efficiently. It offers various helpers for: - aggregating the series data to compute values such as totals, minimums, maximums, and percentages - formatting **numbers and dates** - querying **color, size, and spacing** tokens ## Usage ```tsx import { useChart } from "@chakra-ui/charts" ``` ```tsx const chart = useChart({ data: [ { date: "2024-01-01", revenue: 1000 }, { date: "2024-01-02", revenue: 2000 }, { date: "2024-01-03", revenue: 3000 }, ], series: [{ name: "revenue", color: "blue.500" }], }) ``` ## Series ### `getKey` Returns the key for a given series item. It's an identity function but provides a **typesafe** way to access the series data. ```tsx const key = chart.getKey("revenue") ``` ## Aggregation ### `getTotal` Computes the **total sum** of a given series across all entries. ```tsx console.log(chart.getTotal("revenue")) // 6000 ``` ### `getMin` Finds the **minimum value** for a given key in the dataset. ```tsx console.log(chart.getMin("revenue")) // 1000 ``` ### `getMax` Finds the **maximum value** for a given key in the dataset. ```tsx console.log(chart.getMax("revenue")) // 3000 ``` ### `getValuePercent` Calculates **the percentage** of a value relative to the dataset or a given domain. ```tsx const percentage = chart.getValuePercent("revenue", 5000) console.log(percentage) // 0.5 ``` ## Formatting ### `formatNumber` Formats numbers using the current locale from `EnvironmentProvider` and `Intl.NumberFormatOptions` provided. ```tsx const format = chart.formatNumber({ style: "currency", currency: "USD" }) console.log(format(1000)) // "$1,000.00" ``` ### `formatDate` Formats a date string based on **locale settings**. ```tsx const formatDate = chart.formatDate({ year: "numeric", month: "short" }) console.log(formatDate("2024-03-28")) // "Mar 2024" ``` ## Design Tokens ### `color` Retrieves a **Chakra UI color token**. ```tsx const barColor = chart.color("blue.500") // var(--chakra-colors-blue-500) ``` ### `size` Retrieves a **Chakra UI size token**. ```tsx const chartSize = chart.size("4") // var(--chakra-sizes-4) ``` ### `spacing` Retrieves a **Chakra UI spacing token**. ```tsx const barColor = chart.color("blue.500") // var(--chakra-colors-blue-500) const chartPadding = chart.spacing("4") // var(--chakra-spacing-4) ``` ## Sorting Automatically sorts the chart data based on a specified key and direction. ```tsx /sort: { by: "date", direction: "asc" }/ const chart = useChart({ data: [ { date: "2024-01-01", revenue: 1000 }, { date: "2024-01-02", revenue: 2000 }, { date: "2024-01-03", revenue: 3000 }, ], sort: { by: "date", direction: "asc" }, series: [{ name: "revenue", color: "blue.500" }], }) ``` ## Highlighting When interacting with the chart legends, the series can be highlighted based on `click` or `hover` events. The `highlightedSeries` state is used to track which series is currently highlighted. > This is mostly useful when you have multiple series in the chart. ### `highlightedSeries` Tracks which series is currently highlighted. ### `setHighlightedSeries` Sets the highlighted series. ```tsx chart.setHighlightedSeries("revenue") ``` ### `isHighlightedSeries` Checks if a series is highlighted. ```tsx const isActive = chart.isHighlightedSeries("revenue") ``` ## API Table | Helper | Purpose | | ------------------------------------- | --------------------------------- | | `getSeries(item)` | Finds details of a series item | | `getSeriesOpacity(name, fallback)` | Controls series opacity | | `getTotal(key)` | Computes total sum of a key | | `getMin(key)` | Gets minimum value for a key | | `getMax(key)` | Gets maximum value for a key | | `getValuePercent(key, value, domain)` | Calculates percentage of a value | | `formatNumber(options)` | Formats numbers based on locale | | `formatDate(options)` | Formats dates based on locale | | `color(key)` | Retrieves Chakra UI color token | | `size(key)` | Retrieves Chakra UI size token | | `spacing(key)` | Retrieves Chakra UI spacing token | | `data` | The resolved chart data | | `highlightedSeries` | Tracks highlighted series | | `setHighlightedSeries(name)` | Sets highlighted series | | `isHighlightedSeries(name)` | Checks if a series is highlighted |