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# Usage
Chart.js can be used with ES6 modules, plain JavaScript and module loaders.
## Creating a Chart
To create a chart, we need to instantiate the `Chart` class. To do this, we need to pass in the node, jQuery instance, or 2d context of the canvas of where we want to draw the chart. Here's an example.
```html
< canvas id = "myChart" width = "400" height = "400" > < / canvas >
```
```javascript
// Any of the following formats may be used
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var ctx = document.getElementById('myChart');
var ctx = document.getElementById('myChart').getContext('2d');
var ctx = $('#myChart');
var ctx = 'myChart';
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```
Once you have the element or context, you're ready to instantiate a pre-defined chart-type or create your own!
The following example instantiates a bar chart showing the number of votes for different colors and the y-axis starting at 0.
```html
< canvas id = "myChart" width = "400" height = "400" > < / canvas >
< script >
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var ctx = document.getElementById('myChart');
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var myChart = new Chart(ctx, {
type: 'bar',
data: {
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labels: ['Red', 'Blue', 'Yellow', 'Green', 'Purple', 'Orange'],
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datasets: [{
label: '# of Votes',
data: [12, 19, 3, 5, 2, 3],
backgroundColor: [
'rgba(255, 99, 132, 0.2)',
'rgba(54, 162, 235, 0.2)',
'rgba(255, 206, 86, 0.2)',
'rgba(75, 192, 192, 0.2)',
'rgba(153, 102, 255, 0.2)',
'rgba(255, 159, 64, 0.2)'
],
borderColor: [
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'rgba(255, 99, 132, 1)',
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'rgba(54, 162, 235, 1)',
'rgba(255, 206, 86, 1)',
'rgba(75, 192, 192, 1)',
'rgba(153, 102, 255, 1)',
'rgba(255, 159, 64, 1)'
],
borderWidth: 1
}]
},
options: {
scales: {
yAxes: [{
ticks: {
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beginAtZero: true
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}
}]
}
}
});
< / script >
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```