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--- title: Getting started anchor: getting-started --- ###Include Chart.js First we need to include the Chart.js library on the page. The library occupies a global variable of `Chart`. ```html <script src="Chart.js"></script> ``` Alternatively, if you're using an AMD loader for JavaScript modules, that is also supported in the Chart.js core. Please note: the library will still occupy a global variable of `Chart`, even if it detects `define` and `define.amd`. If this is a problem, you can call `noConflict` to restore the global Chart variable to it's previous owner. ```javascript // Using requirejs require(['path/to/Chartjs'], function(Chart){ // Use Chart.js as normal here. // Chart.noConflict restores the Chart global variable to it's previous owner // The function returns what was previously Chart, allowing you to reassign. var Chartjs = Chart.noConflict(); }); ``` You can also grab Chart.js using bower: ```bash bower install Chart.js --save ``` ###Creating a chart To create a chart, we need to instantiate the `Chart` class. To do this, we need to pass in the 2d context of where we want to draw the chart. Here's an example. ```html <canvas id="myChart" width="400" height="400"></canvas> ``` ```javascript // Get the context of the canvas element we want to select var ctx = document.getElementById("myChart").getContext("2d"); var myNewChart = new Chart(ctx).PolarArea(data); ``` We can also get the context of our canvas with jQuery. To do this, we need to get the DOM node out of the jQuery collection, and call the `getContext("2d")` method on that. ```javascript // Get context with jQuery - using jQuery's .get() method. var ctx = $("#myChart").get(0).getContext("2d"); // This will get the first returned node in the jQuery collection. var myNewChart = new Chart(ctx); ``` After we've instantiated the Chart class on the canvas we want to draw on, Chart.js will handle the scaling for retina displays. With the Chart class set up, we can go on to create one of the charts Chart.js has available. In the example below, we would be drawing a Polar area chart. ```javascript new Chart(ctx).PolarArea(data, options); ``` We call a method of the name of the chart we want to create. We pass in the data for that chart type, and the options for that chart as parameters. Chart.js will merge the global defaults with chart type specific defaults, then merge any options passed in as a second argument after data. ###Global chart configuration This concept was introduced in Chart.js 1.0 to keep configuration DRY, and allow for changing options globally across chart types, avoiding the need to specify options for each instance, or the default for a particular chart type. ```javascript Chart.defaults.global = { // Boolean - Whether to animate the chart animation: true, // Number - Number of animation steps animationSteps: 60, // String - Animation easing effect animationEasing: "easeOutQuart", // Boolean - If we should show the scale at all showScale: true, // Boolean - If we want to override with a hard coded scale scaleOverride: false, // ** Required if scaleOverride is true ** // Number - The number of steps in a hard coded scale scaleSteps: null, // Number - The value jump in the hard coded scale scaleStepWidth: null, // Number - The scale starting value scaleStartValue: null, // String - Colour of the scale line scaleLineColor: "rgba(0,0,0,.1)", // Number - Pixel width of the scale line scaleLineWidth: 1, // Boolean - Whether to show labels on the scale scaleShowLabels: true, // Interpolated JS string - can access value scaleLabel: "<%=value%>", // Boolean - Whether the scale should stick to integers, not floats even if drawing space is there scaleIntegersOnly: true, // Boolean - Whether the scale should start at zero, or an order of magnitude down from the lowest value scaleBeginAtZero: false, // String - Scale label font declaration for the scale label scaleFontFamily: "'Helvetica Neue', 'Helvetica', 'Arial', sans-serif", // Number - Scale label font size in pixels scaleFontSize: 12, // String - Scale label font weight style scaleFontStyle: "normal", // String - Scale label font colour scaleFontColor: "#666", // Boolean - whether or not the chart should be responsive and resize when the browser does. responsive: false, // Boolean - whether to maintain the starting aspect ratio or not when responsive, if set to false, will take up entire container maintainAspectRatio: true, // Boolean - Determines whether to draw tooltips on the canvas or not showTooltips: true, // Function - Determines whether to execute the customTooltips function instead of drawing the built in tooltips (See [Advanced - External Tooltips](#advanced-usage-custom-tooltips)) customTooltips: false, // Array - Array of string names to attach tooltip events tooltipEvents: ["mousemove", "touchstart", "touchmove"], // String - Tooltip background colour tooltipFillColor: "rgba(0,0,0,0.8)", // String - Tooltip label font declaration for the scale label tooltipFontFamily: "'Helvetica Neue', 'Helvetica', 'Arial', sans-serif", // Number - Tooltip label font size in pixels tooltipFontSize: 14, // String - Tooltip font weight style tooltipFontStyle: "normal", // String - Tooltip label font colour tooltipFontColor: "#fff", // String - Tooltip title font declaration for the scale label tooltipTitleFontFamily: "'Helvetica Neue', 'Helvetica', 'Arial', sans-serif", // Number - Tooltip title font size in pixels tooltipTitleFontSize: 14, // String - Tooltip title font weight style tooltipTitleFontStyle: "bold", // String - Tooltip title font colour tooltipTitleFontColor: "#fff", // Number - pixel width of padding around tooltip text tooltipYPadding: 6, // Number - pixel width of padding around tooltip text tooltipXPadding: 6, // Number - Size of the caret on the tooltip tooltipCaretSize: 8, // Number - Pixel radius of the tooltip border tooltipCornerRadius: 6, // Number - Pixel offset from point x to tooltip edge tooltipXOffset: 10, {% raw %} // String - Template string for single tooltips tooltipTemplate: "<%if (label){%><%=label%>: <%}%><%= value %>", {% endraw %} // String - Template string for multiple tooltips multiTooltipTemplate: "<%= value %>", // Function - Will fire on animation progression. onAnimationProgress: function(){}, // Function - Will fire on animation completion. onAnimationComplete: function(){} } ``` If for example, you wanted all charts created to be responsive, and resize when the browser window does, the following setting can be changed: ```javascript Chart.defaults.global.responsive = true; ``` Now, every time we create a chart, `options.responsive` will be `true`.