chart.js
Version:
Simple HTML5 charts using the canvas element.
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Markdown
# 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
var ctx = document.getElementById("myChart");
var ctx = document.getElementById("myChart").getContext("2d");
var ctx = $("#myChart");
var ctx = "myChart";
```
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>
var ctx = document.getElementById("myChart");
var myChart = new Chart(ctx, {
type: 'bar',
data: {
labels: ["Red", "Blue", "Yellow", "Green", "Purple", "Orange"],
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: [
'rgba(255,99,132,1)',
'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: {
beginAtZero:true
}
}]
}
}
});
</script>
```