ChartJS, Primeng, Gap first and end of line chart - javascript

I am using primeng chart component which uses chartjs. We are using chartjs 2.5.0 alongside primeng 4.0 and angular 4.
I created a dynamic chart and I put the data into chart after it came to us through some services. The problem is, after a while chartjs will put a gap at first and end of the chart.
Here is our options for chartjs:
this.options = {
responsive: true,
tooltips: {
mode: 'index',
intersect: false, // all points in chart to show tooltip
callbacks: { // adding labels as title in tooltip
title: function(tooltipItems, data) {
let date = tooltipItems[0].xLabel;
return me._rhDatePipe.transform(date, 'time');
}
}
},
hover : {
mode: 'index',
intersect: false
},
scales: {
xAxes: [{
type: 'time',
display: false, // preventing labels from being displayed
max: 20
}],
yAxes: [{
ticks: {
maxTicksLimit: 3
}
}]
}
}
and here is our first data settings:
this.data = {
labels: this.labels, // current time as label
datasets: [
{
label: me._messageService.translate('chart-label-buy'),
data: this.buyingData,
fill: false,
borderColor: "#2453db",
lineTension: 0,
borderWidth: 1.5,
radius: 0 // removing dot points on chart
},
{
label: me._messageService.translate('chart-label-sale'),
data: this.sellingData,
fill: false,
borderColor: "#f44336",
borderWidth: 1.5,
lineTension: 0,
radius: 0 // removing dot points on chart
},
{
label: me._messageService.translate('chart-label-last-trade'),
data: this.lastPriceData,
fill: false,
borderColor: "#000000",
lineTension: 0,
borderWidth: 1.5,
radius: 0 // removing dot points on chart
}
]
}
and here is the loop which will update the chart:
if(sortedKeysList != null) {
for(let key in sortedKeysList) {
let currentTime: number = sortedKeysList[key];
// just add new points
if(!this.currentTimes.includes(currentTime)) {
let date = new Date(currentTime);
this.labels.push(date);
this.currentTimes.push(currentTime);
this.buyingData.push(this.bestLimitsChart[currentTime].buy);
this.sellingData.push(this.bestLimitsChart[currentTime].sale);
if(this.bestLimitsChart[currentTime].price != 0)
this.lastPriceData.push(this.bestLimitsChart[currentTime].price);
else
this.lastPriceData.push(null);
this.updateChart();
}
}
}
and the picture of chart:
I do not know what is going on. Any helps will greatly appreciated.

I finally found the problem,
for other people facing this issue, you can add unit to your axis:
xAxes: [{
type: 'time',
time: {
displayFormats: {
minute: 'h:mm', // formatting data in labels
},
unit: 'minute' // destroy first and end gaps
},
display: false, // preventing labels from being displayed
}],
similar issue on github:
https://github.com/chartjs/Chart.js/issues/2277#issuecomment-314662961

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The below code in write in laravel php for the chartpie.
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Check the current chart pie below, I tried a lot but I can't find a solution.
How do I add percent sign (%) behind of all values
Thanks
You need to define a tooltips.callback.label function as shown below. For further details please consult Chart.js v. 2.8.0 documentation here.
options: {
...
tooltips: {
callbacks: {
label: (tooltipItem, data) => data.datasets[0].data[tooltipItem.index] + '%'
}
},
...
Please note that you're using a rather old version of Chart.js, the today latest stable version is 3.7.0.

Chart.js Version 3: how to set the different color for tick lines and gridlines

Is there a way to set a different color for chart tick line and gridlines color, using chart.js 3.x? When I change the gridline color then tick color also changes, I want to have a different color for the tick and gridlines.
I tried with the below config, but it changes color for both tick and gridlines.
var config = {
type: 'line',
data: {
datasets: [],
},
options: {
scales: {
xAxes: {
ticks: {
beginAtZero: true
},
gridLines: {
color: "#FFFF00",
zeroLineColor: "#00FFFF",
zeroLineWidth: 1
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yAxes: {
ticks: {
beginAtZero: true
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gridLines: {
color: "#FFFF00",
zeroLineColor: "#00FFFF",
zeroLineWidth: 1
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}
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};
How to use scriptable options to set a different color for tick and gridline?
An easy way is to set Chart.defaults.borderColor to a new value before drawing your chart.
For example:
Chart.defaults.borderColor = "rgba(255,255,255, .2)"; // White translucent, good for dark themes
let chart_options = {
type: 'bar',
data: {
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var ctx = document.getElementById('some-chart').getContext('2d');
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Chart.js : How I change the x axes ticks labels alignment in any sizes?

How can I move my labels on my x axes in between another x axes label. Nothing seems to work and I was unable to find anything on the docs. Is there a workaround? I'm using line chart time series.
https://www.chartjs.org/samples/latest/scales/time/financial.html
Currently, with the code I have its generating the figure below:
var cfg = {
elements:{
point: {
radius: 4
}
},
data: {
datasets: [
{
label: 'vsy',
backgroundColor: color(window.chartColors.red).alpha(0.5).rgbString(),
borderColor: window.chartColors.red,
data: firstData,
type: 'line',
pointRadius: 2,
fill: false,
lineTension: 0,
borderWidth: 2
},
{
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lineTension: 0,
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animation: {
duration: 0
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xAxes: [{
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autoSkipPadding: 75,
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tooltips: {
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This is what I have now:
I want the labels on the x-axis to be on center instead of below the y axis grid line.
Thanks to uminder, with his comment it solves the issue but now I have a conflicting tooltip which lie on a same grid. When I hover to april line first point it shows me mar 30 which lies just above it and vice versa.
I fixed it by changing the mode to nearest but why is it activating the another point?
The option you're looking for is offsetGridLines.
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xAxes: [{
...
gridLines: {
offsetGridLines: true
}
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Please have a look at below runnable code snippet to see how it works.
function generateData() {
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return Math.random() * (max - min) + min;
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var open = randomNumber(lastClose * 0.95, lastClose * 1.05).toFixed(2);
var close = randomNumber(open * 0.95, open * 1.05).toFixed(2);
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}
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var now = moment();
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Chart.scaleService.registerScaleType('timecenter', TimeCenterScale, defaults);
var cfg = {
data: {
datasets: [{
label: 'CHRT - Chart.js Corporation',
backgroundColor: 'red',
borderColor: 'red',
data: generateData(),
type: 'line',
pointRadius: 0,
fill: false,
lineTension: 0,
borderWidth: 2
}]
},
options: {
animation: {
duration: 0
},
scales: {
xAxes: [{
type: 'timecenter',
time: {
unit: 'month',
stepSize: 1,
displayFormats: {
month: 'MMM'
}
},
gridLines: {
offsetGridLines: true
}
}],
yAxes: [{
gridLines: {
drawBorder: false
}
}]
},
tooltips: {
intersect: false,
mode: 'index'
}
}
};
var chart = new Chart('chart1', cfg);
<script src="https://cdnjs.cloudflare.com/ajax/libs/moment.js/2.18.1/moment.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/Chart.js/2.9.3/Chart.min.js"></script>
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scales: {
x: {
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...
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Why does Chartjs line chart does not animate to new values?

I am using a chartjs line chart showing time data where I want to update with new values from an ajax call.
I have time on the X axis (1 days on 15 minutes intervals) , and just numbers for the Y axis.
So it looks like the following..
My setup is as follows.
this.chartSetup = {
type: 'line',
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labels: this.times,
datasets: [{
fill: true,
lineTension: 0.1,
backgroundColor: "rgba(75,192,192,0.4)",
borderColor: "rgba(75,192,192,1)",
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data: this.vals,
pointRadius: 0,
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},
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maintainAspectRatio: false,
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xAxes: [{
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minute: 'h:mm a',
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};
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When the chart first draws it animates the new values. However, if I then remove the data, and add a new set, it does not animate to the new values.
For example, to mimic new server data, using a timer, if I do the following,
where this.times holds the X data, this.vals holds the Y..
setTimeout(() => {
let temp = this.makeDummyData(20);
//let dataToUpdate = (<any>(this.chart.data)).datasets[0].data;
//let labels = (<any>(this.chart.data)).labels;
this.times.splice(0, this.times.length);
this.vals.splice(0, this.vals.length);
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this.times.push(item.time);
this.vals.push(item.val);
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this.chart.update();
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The chart does update, but it does not have any animation, it just jumps straight to the new display. If I just date the exiting data without removing it first, does does animate to the new display.
Is there any reason the animation does not work when I replace the data as in the above example?
Thanks in advance for any suggestions

Chartjs X axis label and tick formatting

I am using Chartjs to display a time series line graph.
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this.chartSetup = {
type: 'line',
data: {
labels: this.times,
datasets: [{
fill: true,
lineTension: 0.1,
backgroundColor: "rgba(75,192,192,0.4)",
borderColor: "rgba(75,192,192,1)",
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}
},
tooltips: {
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},
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maintainAspectRatio: false,
scales: {
xAxes: [{
ticks: {
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unitStepSize: 5
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hour: 'h:mm a',
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My chart looks like the following screen shot
The data is Date for the X axis (Labels), and just numbers for the Y.
The time data goes from 6am to 6pm (12 hours worth)
I have a couple of issues here all relating to the X axis label formatting.
The initial 6am label is being cut off
How can I change the X axis label rotation (so perhaps by 90 degrees will fix the truncated first value)
My data goes to 6pm, but it is showing an extra X axis value (7pm). Can I get rid of this?
Thanks in advance for any suggestions here.
What worked for me was setting
autoskip: true
autoSkipPadding: 30
in the tick configuration.
1,2 - set minRotation = 90
3 - set Max value on your x axes

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