# Visualization: Pie Chart ## Overview A pie chart that is rendered within the browser using [SVG](http://www.w3.org/Graphics/SVG/) or [VML](http://en.wikipedia.org/wiki/Vector_Markup_Language). Displays tooltips when hovering over slices. ## Example \

``` ## Making a 3D Pie Chart If you set the `is3D` option to `true`, your pie chart will be drawn as though it has three dimensions: `is3D` is `false` by default, so here we explicitly set it to `true`: ```

``` ## Making a Donut Chart A *donut* chart is a pie chart with a hole in the center. You can create donut charts with the `pieHole` option: The `pieHole` option should be set to a number between 0 and 1, corresponding to the ratio of radii between the hole and the chart. Numbers between 0.4 and 0.6 will look best on most charts. Values equal to or greater than 1 will be ignored, and a value of 0 will completely shut your piehole. ```

``` You can't combine the `pieHole` and `is3D` options; if you do, `pieHole` will be ignored. Note that Google Charts tries to place the label as close to the center of the slice as possible. If you have a donut chart with just one slice, the center of the slice may fall into the donut hole. In that case, change the color of the label: \

``` ## Rotating a Pie Chart By default, pie charts begin with the left edge of the first slice pointing straight up. You can change that with the `pieStartAngle` option:
Here, we rotate the chart clockwise 100 degrees with an option of `pieStartAngle: 100`. (So chosen because that particular angle happens to make the "Italian" label fit inside the slice.) ```

``` ## Exploding a Slice You can separate pie slices from the rest of the chart with the `offset` property of the `slices` option: To separate a slice, create a `slices` object and assign the appropriate slice number an `offset` between 0 and 1. Below, we assign progressively larger offsets to slices 4 (Gujarati), 12 (Marathi), 14 (Oriya), and 15 (Punjabi): ```

``` ## Removing Slices To omit a slice, change the color to `'transparent'`: We also used the `pieStartAngle` to rotate the chart 135 degrees, `pieSliceText` to remove the text from the slices, and `tooltip.trigger` to disable tooltips: ```

``` ## Slice Visibility Threshold You can set a value as the threshold for a pie slice to render individually. This value corresponds to a fraction of the chart (with the whole chart being of value 1). To set this threshold as a percentage of the whole, divide the percentage desired by 100 (for a 20% threshold, the value would be 0.2). ``` sliceVisibilityThreshold: 5/8 // This is equivalent to 0.625 or 62.5% of the chart. ``` Any slices smaller than this threshold will be combined into a single "Other" slice, and will have the combined value of all slices below the threshold. ``` google.charts.load('current', {'packages':['corechart']}); google.charts.setOnLoadCallback(drawChart); function drawChart() { var data = new google.visualization.DataTable(); data.addColumn('string', 'Pizza'); data.addColumn('number', 'Populartiy'); data.addRows([ ['Pepperoni', 33], ['Hawaiian', 26], ['Mushroom', 22], ['Sausage', 10], // Below limit. ['Anchovies', 9] // Below limit. ]); var options = { title: 'Popularity of Types of Pizza', sliceVisibilityThreshold: .2 }; var chart = new google.visualization.PieChart(document.getElementById('chart_div')); chart.draw(data, options); } ``` ## Loading The `google.charts.load` package name is `"corechart"`. ``` google.charts.load("current", {packages: ["corechart"]}); ``` The visualization's class name is `google.visualization.PieChart`. ``` var visualization = new google.visualization.PieChart(container); ``` ## Data Format **Rows:** Each row in the table represents a slice. **Columns:** | | Column 0 | Column 1 | ... | Column *N* (optional) | | Purpose: | Slice labels | Slice values | ... | Optional roles | | Data Type: | string | number | ... | | | Role: | domain | data | ... | | | Optional [column roles](https://developers.google.com/chart/interactive/docs/roles): | *None* | *None* | ... | - [tooltip](https://developers.google.com/chart/interactive/docs/roles#tooltiprole) | |---|---|---|---|---| ## Configuration Options | Name || |---|---| | backgroundColor | The background color for the main area of the chart. Can be either a simple HTML color string, for example: `'red'` or `'#00cc00'`, or an object with the following properties. **Type:** string or object **Default:** 'white' | | backgroundColor.stroke | The color of the chart border, as an HTML color string. **Type:** string **Default:** '#666' | | backgroundColor.strokeWidth | The border width, in pixels. **Type:** number **Default:** 0 | | backgroundColor.fill | The chart fill color, as an HTML color string. **Type:** string **Default:** 'white' | | chartArea | An object with members to configure the placement and size of the chart area (where the chart itself is drawn, excluding axis and legends). Two formats are supported: a number, or a number followed by %. A simple number is a value in pixels; a number followed by % is a percentage. Example: `chartArea:{left:20,top:0,width:'50%',height:'75%'}` **Type:** object **Default:** null | | chartArea.backgroundColor | Chart area background color. When a string is used, it can be either a hex string (e.g., '#fdc') or an English color name. When an object is used, the following properties can be provided: - `stroke`: the color, provided as a hex string or English color name. - `strokeWidth`: if provided, draws a border around the chart area of the given width (and with the color of `stroke`). **Type:** string or object **Default:** 'white' | | chartArea.left | How far to draw the chart from the left border. **Type:** number or string **Default:** auto | | chartArea.top | How far to draw the chart from the top border. **Type:** number or string **Default:** auto | | chartArea.width | Chart area width. **Type:** number or string **Default:** auto | | chartArea.height | Chart area height. **Type:** number or string **Default:** auto | | colors | The colors to use for the chart elements. An array of strings, where each element is an HTML color string, for example: `colors:['red','#004411']`. **Type:** Array of strings **Default:** default colors | | enableInteractivity | Whether the chart throws user-based events or reacts to user interaction. If false, the chart will not throw 'select' or other interaction-based events (but *will* throw ready or error events), and will not display hovertext or otherwise change depending on user input. **Type:** boolean **Default:** true | | fontSize | The default font size, in pixels, of all text in the chart. You can override this using properties for specific chart elements. **Type:** number **Default:** automatic | | fontName | The default font face for all text in the chart. You can override this using properties for specific chart elements. **Type:** string **Default:** 'Arial' | | forceIFrame | Draws the chart inside an inline frame. (Note that on IE8, this option is ignored; all IE8 charts are drawn in i-frames.) **Type:** boolean **Default:** false | | height | Height of the chart, in pixels. **Type:** number **Default:** height of the containing element | | is3D | If true, displays a three-dimensional chart. **Type:** boolean **Default:** false | | legend | An object with members to configure various aspects of the legend. To specify properties of this object, you can use object literal notation, as shown here: ``` {position: 'top', textStyle: {color: 'blue', fontSize: 16}} ``` **Type:** object **Default:** null | | legend.alignment | Alignment of the legend. Can be one of the following: - 'start' - Aligned to the start of the area allocated for the legend. - 'center' - Centered in the area allocated for the legend. - 'end' - Aligned to the end of the area allocated for the legend. Start, center, and end are relative to the style -- vertical or horizontal -- of the legend. For example, in a 'right' legend, 'start' and 'end' are at the top and bottom, respectively; for a 'top' legend, 'start' and 'end' would be at the left and right of the area, respectively. The default value depends on the legend's position. For 'bottom' legends, the default is 'center'; other legends default to 'start'. **Type:** string **Default:** automatic | | legend.position | Position of the legend. Can be one of the following: - 'bottom' - Displays the legend below the chart. - 'labeled' - Draws lines connecting slices to their data values. - 'left' - Displays the legend left of the chart. - 'none' - Displays no legend. - 'right' - Displays the legend right of the chart. - 'top' - Displays the legend above the chart. **Type:** string **Default:** 'right' | | legend.maxLines | Maximum number of lines in the legend. Set this to a number greater than one to add lines to your legend. Note: The exact logic used to determine the actual number of lines rendered is still in flux. This option currently works only when legend.position is 'top'. **Type:** number **Default:** 1 | | legend.textStyle | An object that specifies the legend text style. The object has this format: ``` { color: , fontName: , fontSize: , bold: , italic: } ``` The `color` can be any HTML color string, for example: `'red'` or `'#00cc00'`. Also see `fontName` and `fontSize`. **Type:** object **Default:** ` {color: 'black', fontName: , fontSize: } ` | | pieHole | If between 0 and 1, displays a donut chart. The hole with have a radius equal to `number` times the radius of the chart. **Type:** number **Default:** 0 | | pieSliceBorderColor | The color of the slice borders. Only applicable when the chart is two-dimensional. **Type:** string **Default:** 'white' | | pieSliceText | The content of the text displayed on the slice. Can be one of the following: - 'percentage' - The percentage of the slice size out of the total. - 'value' - The quantitative value of the slice. - 'label' - The name of the slice. - 'none' - No text is displayed. **Type:** string **Default:** 'percentage' | | pieSliceTextStyle | An object that specifies the slice text style. The object has this format: ``` {color: , fontName: , fontSize: } ``` The `color` can be any HTML color string, for example: `'red'` or `'#00cc00'`. Also see `fontName` and `fontSize`. **Type:** object **Default:** ` {color: 'black', fontName: , fontSize: } ` | | pieStartAngle | The angle, in degrees, to rotate the chart by. The default of `0` will orient the leftmost edge of the first slice directly up. **Type:** number **Default:** `0` | | reverseCategories | If true, draws slices counterclockwise. The default is to draw clockwise. **Type:** boolean **Default:** false | | pieResidueSliceColor | Color for the combination slice that holds all slices below *sliceVisibilityThreshold.* **Type:** string **Default:** '#ccc' | | pieResidueSliceLabel | A label for the combination slice that holds all slices below *sliceVisibilityThreshold*. **Type:** string **Default:** 'Other' | | slices | An array of objects, each describing the format of the corresponding slice in the pie. To use default values for a slice, specify an empty object (i.e., `{}`). If a slice or a value is not specified, the global value will be used. Each object supports the following properties: - `color` - The color to use for this slice. Specify a valid HTML color string. - `offset` - How far to separate the slice from the rest of the pie, from 0.0 (not at all) to 1.0 (the pie's radius). - `textStyle` - Overrides the global `pieSliceTextStyle` for this slice. You can specify either an array of objects, each of which applies to the slice in the order given, or you can specify an object where each child has a numeric key indicating which slice it applies to. For example, the following two declarations are identical, and declare the first slice as black and the fourth as red: ``` slices: [{color: 'black'}, {}, {}, {color: 'red'}] slices: {0: {color: 'black'}, 3: {color: 'red'}} ``` **Type:** Array of objects, or object with nested objects **Default:** {} | | sliceVisibilityThreshold | The fractional value of the pie, below which a slice will not show individually. All slices that have not passed this threshold will be combined to a single "Other" slice, whose size is the sum of all their sizes. Default is not to show individually any slice which is smaller than half a degree. ``` // Slices less than 25% of the pie will be // combined into an "Other" slice. sliceVisibilityThreshold: .25 ``` **Type:** number **Default:** Half a degree (.5/360 or 1/720 or .0014) | | title | Text to display above the chart. **Type:** string **Default:** no title | | titleTextStyle | An object that specifies the title text style. The object has this format: ``` { color: , fontName: , fontSize: , bold: , italic: } ``` The `color` can be any HTML color string, for example: `'red'` or `'#00cc00'`. Also see `fontName` and `fontSize`. **Type:** object **Default:** ` {color: 'black', fontName: , fontSize: } ` | | tooltip | An object with members to configure various tooltip elements. To specify properties of this object, you can use object literal notation, as shown here: ``` {textStyle: {color: '#FF0000'}, showColorCode: true} ``` **Type:** object **Default:** null | | tooltip.ignoreBounds | If set to `true`, allows the drawing of tooltips to flow outside of the bounds of the chart on all sides. **Note:** This only applies to HTML tooltips. If this is enabled with SVG tooltips, any overflow outside of the chart bounds will be cropped. See [Customizing Tooltip Content](https://developers.google.com/chart/interactive/docs/customizing_tooltip_content) for more details. **Type:** boolean **Default:** false | | tooltip.isHtml | If set to true, use HTML-rendered (rather than SVG-rendered) tooltips. See [Customizing Tooltip Content](https://developers.google.com/chart/interactive/docs/customizing_tooltip_content) for more details. **Note:** customization of the HTML tooltip content via the [tooltip column data role](https://developers.google.com/chart/interactive/docs/roles#tooltiprole) is **not** supported by the [Bubble Chart](https://developers.google.com/chart/interactive/docs/gallery/bubblechart) visualization. **Type:** boolean **Default:** false | | tooltip.showColorCode | If true, show colored squares next to the slice information in the tooltip. **Type:** boolean **Default:** false | | tooltip.text | What information to display when the user hovers over a pie slice. The following values are supported: - 'both' - \[*Default*\] Display both the absolute value of the slice and the percentage of the whole. - 'value' - Display only the absolute value of the slice. - 'percentage' - Display only the percentage of the whole represented by the slice. **Type:** string **Default:** 'both' | | tooltip.textStyle | An object that specifies the tooltip text style. The object has this format: ``` { color: , fontName: , fontSize: , bold: , italic: } ``` The `color` can be any HTML color string, for example: `'red'` or `'#00cc00'`. Also see `fontName` and `fontSize`. **Type:** object **Default:** ` {color: 'black', fontName: , fontSize: } ` | | tooltip.trigger | The user interaction that causes the tooltip to be displayed: - 'focus' - The tooltip will be displayed when the user hovers over the element. - 'none' - The tooltip will not be displayed. - 'selection' - The tooltip will be displayed when the user selects the element. **Type:** string **Default:** 'focus' | | width | Width of the chart, in pixels. **Type:** number **Default:** width of the containing element | ## Methods | Method || |---|---| | `draw(data, options)` | Draws the chart. The chart accepts further method calls only after the [`ready`](https://developers.google.com/chart/interactive/docs/gallery/piechart#Events)event is fired. [`Extended description`](https://developers.google.com/chart/interactive/docs/reference#visdraw). **Return Type:** none | | `getAction(actionID)` | Returns the tooltip action object with the requested `actionID`. **Return Type:** object | | `getBoundingBox(id)` | Returns an object containing the left, top, width, and height of chart element `id`. The format for `id` isn't yet documented (they're the return values of [event handlers](https://developers.google.com/chart/interactive/docs/events)), but here are some examples: > `var cli = chart.getChartLayoutInterface();` > Height of the chart area > : `cli.getBoundingBox('chartarea').height` > Width of the third bar in the first series of a bar or column chart > : `cli.getBoundingBox('bar#0#2').width` > Bounding box of the fifth wedge of a pie chart > : `cli.getBoundingBox('slice#4')` > Bounding box of the chart data of a vertical (e.g., column) chart: > : `cli.getBoundingBox('vAxis#0#gridline')` > Bounding box of the chart data of a horizontal (e.g., bar) chart: > : `cli.getBoundingBox('hAxis#0#gridline')` Values are relative to the container of the chart. Call this *after* the chart is drawn. **Return Type:** object | | `getChartAreaBoundingBox()` | Returns an object containing the left, top, width, and height of the chart content (i.e., excluding labels and legend): > `var cli = chart.getChartLayoutInterface();` > : `cli.getChartAreaBoundingBox().left` > : `cli.getChartAreaBoundingBox().top` > : `cli.getChartAreaBoundingBox().height` > : `cli.getChartAreaBoundingBox().width` Values are relative to the container of the chart. Call this *after* the chart is drawn. **Return Type:** object | | `getChartLayoutInterface()` | Returns an object containing information about the onscreen placement of the chart and its elements. The following methods can be called on the returned object: - `getBoundingBox` - `getChartAreaBoundingBox` - `getHAxisValue` - `getVAxisValue` - `getXLocation` - `getYLocation` Call this *after* the chart is drawn. **Return Type:** object | | `getHAxisValue(xPosition, optional_axis_index)` | Returns the horizontal data value at `xPosition`, which is a pixel offset from the chart container's left edge. Can be negative. Example: `chart.getChartLayoutInterface().getHAxisValue(400)`. Call this *after* the chart is drawn. **Return Type:** number | | `getImageURI()` | Returns the chart serialized as an image URI. Call this *after* the chart is drawn. See [Printing PNG Charts](https://developers.google.com/chart/interactive/docs/printing). **Return Type:** string | | `getSelection()` | Returns an array of the selected chart entities. Selectable entities are slices and legend entries. For this chart, only one entity can be selected at any given moment. [`Extended description`](https://developers.google.com/chart/interactive/docs/reference#visgetselection). **Return Type:** Array of selection elements | | `getVAxisValue(yPosition, optional_axis_index)` | Returns the vertical data value at `yPosition`, which is a pixel offset down from the chart container's top edge. Can be negative. Example: `chart.getChartLayoutInterface().getVAxisValue(300)`. Call this *after* the chart is drawn. **Return Type:** number | | `getXLocation(dataValue, optional_axis_index)` | Returns the pixel x-coordinate of `dataValue` relative to the left edge of the chart's container. Example: `chart.getChartLayoutInterface().getXLocation(400)`. Call this *after* the chart is drawn. **Return Type:** number | | `getYLocation(dataValue, optional_axis_index)` | Returns the pixel y-coordinate of `dataValue` relative to the top edge of the chart's container. Example: `chart.getChartLayoutInterface().getYLocation(300)`. Call this *after* the chart is drawn. **Return Type:** number | | `removeAction(actionID)` | Removes the tooltip action with the requested `actionID` from the chart. **Return Type:** `none` | | `setAction(action)` | Sets a tooltip action to be executed when the user clicks on the action text. The `setAction` method takes an object as its action parameter. This object should specify 3 properties: `id`--- the ID of the action being set, `text` ---the text that should appear in the tooltip for the action, and `action` --- the function that should be run when a user clicks on the action text. Any and all tooltip actions should be set prior to calling the chart's `draw()` method. [Extended description](https://developers.google.com/chart/interactive/docs/reference#vissetaction). **Return Type:** `none` | | `setSelection()` | Selects the specified chart entities. Cancels any previous selection. Selectable entities are slices and legend entries. For this chart, only one entity can be selected at a time. [`Extended description`](https://developers.google.com/chart/interactive/docs/reference#vissetselection). **Return Type:** none | | `clearChart()` | Clears the chart, and releases all of its allocated resources. **Return Type:** none | ## Events For more information on how to use these events, see [Basic Interactivity](https://developers.google.com/chart/interactive/docs/basic_interactivity), [Handling Events](https://developers.google.com/chart/interactive/docs/events), and [Firing Events](https://developers.google.com/chart/interactive/docs/dev/events). | Name || |---|---| | `click` | Fired when the user clicks inside the chart. Can be used to identify when the title, data elements, legend entries, axes, gridlines, or labels are clicked. **Properties:** targetID | | `error` | Fired when an error occurs when attempting to render the chart. **Properties:** id, message | | `onmouseover` | Fired when the user mouses over a visual entity. Passes back the row and column indices of the corresponding data table element. A slice or legend entry correlates to a row in the data table (column index is null). **Properties:** row, column | | `onmouseout` | Fired when the user mouses away from a visual entity. Passes back the row and column indices of the corresponding data table element. A slice or legend entry correlates to a row in the data table (column index is null). **Properties:** row, column | | `ready` | The chart is ready for external method calls. If you want to interact with the chart, and call methods after you draw it, you should set up a listener for this event *before* you call the `draw` method, and call them only after the event was fired. **Properties:** none | | `select` | Fired when the user clicks a visual entity. To learn what has been selected, call [`getSelection()`](https://developers.google.com/chart/interactive/docs/gallery/piechart#Methods). **Properties:** none | ## Data Policy All code and data are processed and rendered in the browser. No data is sent to any server.