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Chart.JS: How to make sharp lines to smooth curved lines

Hi I'm new at charts and this is my chartjs chart, it's working currently, but it's showing in sharp lines and I want to make it smooth curve lines on this chart. Any ideas?
function statistics(data) {
if ($('#stats-currency').length > 0) {
if (typeof(stats_currency) !== 'undefined') {
stats_currency.destroy();
}
if (typeof(data) == 'undefined') {
var currency = $('select[name="currency"]').val();
$.get(admin_url + 'home/stats_currency/' + currency, function(response) {
stats_currency = new Chart($('#stats-currency'), {
type: 'line',
data: response,
options: {
responsive:true,
scales: {
yAxes: [{
ticks: {
beginAtZero: true,
}
}]
},
},
});
}, 'json');
} else {
stats_currency = new Chart($('#stats-currency'), {
type: 'line',
data: data,
options: {
responsive: true,
scales: {
yAxes: [{
ticks: {
beginAtZero: true,
}
}]
},
},
});
}

This can be done through the option lineTension that needs to be defined on your dataset. Choose a value below 1.
datasets: [{
...
lineTension: 0.8
}]
By default, you should however already see curved smooth lines since accoring to Chart.js documentation, the default value is 0.4.
lineTension: Bezier curve tension of the line. Set to 0 to draw straight lines.
Please note that if the steppedLine value is set to anything other than false, lineTension will be ignored.

you can do it by adding tension value to your charts options
<canvas id="myChart"></canvas>
JS
const config = {
type: 'line', // your chart type
data: data, // pass here your data
options: {
elements: {
line: {
tension : 0.4 // smooth lines
},
},
},
};
// pass it like
const myChart = new Chart(
document.getElementById('myChart'),
config
);

ChartJs - Labelling minimum and maximum value of the Y Axis

I found a code to add a label to each value in the Y axis and I have tried it. This is the code
var chart = new Chart(ctx, {
type: 'line',
data: data,
options: {
scales: {
yAxes: [{
ticks: {
// Include a dollar sign in the ticks
callback: function(value, index, values) {
return '$' + value;
}
}
}]
}
}
});
But, can I give it only for minimum and maximum values? If so, how?
The following is an example chart that I mean. The minimum and maximum labels I give a red mark.
Example chart that I mean

You can specify min and max directly, Please check https://www.chartjs.org/docs/latest/axes/cartesian/linear.html#step-size
e.g
var chart = new Chart(ctx, {
type: 'line',
data: data,
options: {
scales: {
yAxes: [{
ticks: {
// Include a dollar sign in the ticks
callback: function(value, index, values) {
return '$' + value;
},
min: 1,
max: 100
}
}]
}
}});
You can also use axis range settings, It is only change the data values that are used to scale the axis and useful for extending the range of the axis while maintaining the auto fit behaviour.
https://www.chartjs.org/docs/latest/axes/cartesian/linear.html#axis-range-settings
e.g.
var chart = new Chart(ctx, {
type: 'line',
data: data,
options: {
scales: {
yAxes: [{
ticks: {
// Include a dollar sign in the ticks
callback: function(value, index, values) {
return '$' + value;
},
suggestedMin: 1,
suggestedMax: 100
}
}]
}
}});

Make Chart.js horizontal bar labels multi-line

Just wondering if there is any way to set the horizontal bar labels for y-axis using chart.js. Here is how I set up the chart:
<div class="box-body">
<canvas id="chart" style="position: relative; height: 300px;"></canvas>
</div>
Javascript:
var ctx = document.getElementById('chart').getContext("2d");
var options = {
layout: {
padding: {
top: 5,
}
},
responsive: true,
animation: {
animateScale: true,
animateRotate: true
},
};
var opt = {
type: "horizontalBar",
data: {
labels: label,
datasets: [{
data: price,
}]
},
options: options
};
if (chart) chart.destroy();
chart= new Chart(ctx, opt);
chart.update();
As you all can see, the first and third labels are too long and cut off. Is there a way to make the label multi-line?

If you want to have full control over how long labels are broken down across lines you can specify the breaking point by providing labels in a nested array. For example:
var chart = new Chart(ctx, {
...
data: {
labels: [["Label1 Line1:","Label1 Line2"],["Label2 Line1","Label2 Line2"]],
datasets: [{
...
});

You can use the following chart plugin :
plugins: [{
beforeInit: function(chart) {
chart.data.labels.forEach(function(e, i, a) {
if (/\n/.test(e)) {
a[i] = e.split(/\n/);
}
});
}
}]
add this followed by your chart options
ᴜꜱᴀɢᴇ :
add a new line character (\n) to your label, wherever you wish to add a line break.
ᴅᴇᴍᴏ
var chart = new Chart(ctx, {
type: 'horizontalBar',
data: {
labels: ['Jan\n2017', 'Feb', 'Mar', 'Apr'],
datasets: [{
label: 'BAR',
data: [1, 2, 3, 4],
backgroundColor: 'rgba(0, 119, 290, 0.7)'
}]
},
options: {
scales: {
xAxes: [{
ticks: {
beginAtZero: true
}
}]
}
},
plugins: [{
beforeInit: function(chart) {
chart.data.labels.forEach(function(e, i, a) {
if (/\n/.test(e)) {
a[i] = e.split(/\n/);
}
});
}
}]
});
<script src="https://cdnjs.cloudflare.com/ajax/libs/Chart.js/2.6.0/Chart.min.js"></script>
<canvas id="ctx"></canvas>

Chartjs - Set start and end value into a Bar Chart

I am working on drowing a Gantt diagram like on Chartjs.
What am I trying to do is painting and HorizontalBarChart with time type, as a mixed type where I set a min value for each bar, however seems it does not work.
My code:
new Chart(document.getElementById("customChart"), {
type: 'horizontalBar',
data: {
labels: ['Item 1', 'Item 2'],
datasets: [
{
type: 'horizontalBar',
label: 'Bar Component1',
data: [new Date(2017,02,26) ],
options:{
scales:{
xAxes: [{
type: 'time',
unit: 'day',
unitStepSize: 1,
time: {
displayFormats: {
'day': 'YYYY-MM-DD'
},
min: new Date(2017,03,24)
}
}]
}
}
},
{
type: 'horizontalBar',
label: 'Bar Component2',
data: [new Date(2017,02,14)],
options:{
scales:{
xAxes: [{
type: 'time',
unit: 'day',
unitStepSize: 1,
time: {
displayFormats: {
'day': 'YYYY-MM-DD'
},
min: new Date(2017,02,10)
}
}]
}
}
}
]
}
});
Is there any workaround in order to implement this? Should I use another library?

Unfortunately, there is no way to configure chart.js to produce a gantt chart because each dataset that you plot on the graph either starts at the origin (the min value set on the scale) or is stacked right on top of each other. You cannot configure a chart to stack bars but show them in different "lanes" (which is what a gantt chart would require).
Even if you try to create multiple scales (which is looks like you are attempting), it will not work because the 2nd bar will still start at the origin (however the 2nd scale's origin would be the min value you specified). In other words, both bars will still touch the y axis.
You had several problems with you chart.js configuration. First, you cannot define scale config in a dataset. Second, you tried to use several time scale options, but they must be inside the time object.
I cleaned up everything just so you can see how to correctly define a chart. Here is a codepen demonstrating this.

Currently [November 2018] chart.js is not able todo so.
However if you are willing to apply a patch, there is a pull request pending, which would implement exactly this feature: https://github.com/chartjs/Chart.js/pull/5262
For my purposes I adapted the code of https://github.com/chartjs/Chart.js/blob/master/src/controllers/controller.bar.js
## -453,10 +453,12 ## module.exports = function(Chart) {
helpers.canvas.clipArea(chart.ctx, chart.chartArea);
- for (; i < ilen; ++i) {
- if (!isNaN(scale.getRightValue(dataset.data[i]))) {
- rects[i].draw();
- }
+ if (dataset.label != 'noshow') {
+ for (; i < ilen; ++i) {
+ if (!isNaN(scale.getRightValue(dataset.data[i]))) {
+ rects[i].draw();
+ }
+ }
}
helpers.canvas.unclipArea(chart.ctx);
Utilizing bar chart like this:
var gapdemo= new Chart(ctx, {
type: 'horizontalBar',
data: {
labels: ["todo1", "todo2", "todo3", "todo4"],
datasets: [{
type: 'horizontalBar',
label: 'noshow',
data: [1,2,4,3],
},{
type: 'horizontalBar',
label: 'showme',
data: [3,2,2,1],
},{
type: 'horizontalBar',
label: 'noshow',
data: [1,5,3,4],
},{
type: 'horizontalBar',
label: 'showme',
data: [2,2,1,4],
}]
},
options: {
scales: {
xAxes: [{
id: 'x-axis-1',
stacked: true
}],
yAxes: [{
id: 'y-axis-1',
stacked: true,
ticks: {beginAtZero: true}
}]
}
}
});
This results in a chart like that:
barchart with gaps

Since version 2.9.0, Chart.js supports floating bars. Individual bars can now be specified with the syntax [min, max].
This makes it possible to draw a Gantt chart.
var dates = [new Date("2019-12-24"), new Date("2019-12-26"), new Date("2019-12-30"), new Date("2020-1-2"), new Date("2020-1-4"), new Date("2020-1-9"), new Date("2020-1-10") ];
var ctx = document.getElementById("myChart").getContext('2d');
var myChart = new Chart(ctx, {
type: 'horizontalBar',
data: {
labels: dates.map((d, i) => "Task " + i).splice(1),
datasets: [
{
label: 'Tasks',
data: dates.map((d, i) => i == 0 ? null : [dates[i - 1], d]).slice(1),
backgroundColor: 'lightblue',
borderWidth: 1
}
]
},
options: {
responsive: true,
scales: {
xAxes: [{
type: 'time',
time: {
displayFormats: {
day: 'YYYY-MM-DD'
}
},
ticks: {
min: dates[0].getTime(),
max: dates[dates.length - 1].getTime()
}
}]
}
}
});
<script src="https://cdnjs.cloudflare.com/ajax/libs/moment.js/2.1.0/moment.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/Chart.js/2.9.3/Chart.min.js"></script>
<canvas id="myChart"></canvas>

Chart Js change y axis to real number

I am using latest chart js and i want to change Y axis value to real number
0,1,2,3,....
i want to change y axis in to positive real numbers where do i put scales value to change above format to real number format
var ctx = document.getElementById("myChart");
var myChart = new Chart(ctx, {
type: 'bar',
data: {
labels: allDate,
datasets:jsonArray,
},
options: {
scales: {
xAxes: [{
display:true
}],
yAxes: [{
display:true,
type: "linear",
ticks: {
userCallback: function(value, index, values) {
return value;
}
}
}]
}
}
});