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Remove grid lines and numbers on Chart.js

I am trying to remove the grid lines on the Radar chart on chart.js v2 for react.
Desired Result
but keeping the outermost line while removing the inner lines and numbers
I have attempted to use the following code but it only returns a runtime error saying "category" is not a registered scale.
const options = {
scales: {
x: {
grid: {
display: false
}
},
y: {
grid: {
display: false
}
}
}
}

This can be done through the following options.
scale: {
ticks: {
stepSize: 1,
callback: (v, i, values) => i + 1 < values.length ? '' : v
},
gridLines: {
color: [0, 0, 0, 0, '#ccc']
}
}
For further details, please consult the Styling page from the Chart.js v2.9.4 documentation.
Please take a look at below runnable code and see how it works. Note that it uses a generic approach for defining gridLines.color.
const labels = ['Things 1', 'Things 2', 'Things 3', 'Things 4', 'Things 5'];
const data = [0, 3, 5, 2, 5];
const max = Math.ceil(Math.max(...data));
new Chart('radar-chart', {
type: 'radar',
data: {
labels: labels,
datasets: [{
data: data,
fill: true,
backgroundColor: 'rgba(0, 0, 255,0.2)',
borderColor: 'rgb(0, 0, 255)'
}]
},
options: {
legend: {
display: false
},
scale: {
ticks: {
stepSize: 1,
max: max,
callback: (v, i, values) => i + 1 < values.length ? '' : v
},
gridLines: {
color: Array.from(Array(max).keys()).map((v, i) => i + 1 < max ? 0 : '#ccc')
}
}
}
});
<script src="https://cdnjs.cloudflare.com/ajax/libs/Chart.js/2.9.4/Chart.js"></script>
<canvas id="radar-chart" height="80"></canvas>

From the error you are getting it seems like you are using Chart.js V3 and not V2. To get what you want you need to import and register everything if you want to use treeshaking, I suggest you do this at the latest part and for development import everything like so:
import Chart from 'chart.js/auto';
To hide and get the result what you want your config needs to look like this:
const labels = ['Things 1', 'Things 1', 'Things 1', 'Things 1', 'Things 1'];
const data = [0, 3, 5, 2, 3];
new Chart('radar-chart', {
type: 'radar',
data: {
labels: labels,
datasets: [{
data: data,
fill: true,
backgroundColor: 'rgba(0, 0, 255,0.2)',
borderColor: 'rgb(0, 0, 255)'
}]
},
options: {
plugins: {
legend: {
display: false
}
},
scales: {
r: {
ticks: {
stepSize: 1,
callback: (v, i, values) => i + 1 < values.length ? '' : v
},
grid: {
color: data.map((v, i) => i + 1 < data.length ? 0 : '#ccc')
}
}
}
}
});
<script src="https://cdnjs.cloudflare.com/ajax/libs/Chart.js/3.8.0/chart.js"></script>
<canvas id="radar-chart" height="80"></canvas>
Notice that I specify a r scale instead of x and y

Chartjs - make line start at ... but maintain x-axis data

I created a dynamic line chart based on some input data. The intention is that the customer can indicate with a dropdown on which month the "Investment" should start.
So, for example, if the "Investment" does not start until month 6, then that line should only start at 6 on the x-axis. But the other lines "Case" and "ROI" should still just start at 1.
I've tried several things but to no avail.
I tried changing the x-axis "min ticks" based on the selection the user made, but that makes all lines start at another point instead of the "Investment" line only. Another problem is that every number before the selection then dissapears from the x-axis. But I really want to keep every number from 1-60, even if the user chooses to start the "Investment" on month 10, for example.
I would really appreciate some help! Thanks.
Here's my fiddle: https://jsfiddle.net/js5pha24/
var options = {
type: 'line',
data: {
labels: [],
datasets: [{
label: 'Case',
data: [],
backgroundColor: 'rgba(152,164,135, 0.5)',
borderColor: 'rgb(152,164,135)',
fill: false
}, {
label: 'Case',
data: [],
backgroundColor: 'rgba(145,139,167, 0.5)',
borderColor: 'rgb(145,139,167)',
fill: false
}, {
label: 'Case',
data: [],
backgroundColor: 'rgba(206,157,206, 0.5)',
borderColor: 'rgb(206,157,206)',
fill: false
}]
},
options: {
legend: {
display: true,
position: "top"
},
scales: {
xAxes: [{
ticks: {
beginAtZero: true,
autoSkip: true,
maxRotation: 0,
minRotation: 0
}
}],
yAxes: [{
ticks: {
callback: value => {
return "€ " + value;
}
}
}]
}
}
}
for (let i = 1; i <= 60; i++) {
options.data.labels.push(i);
const caseMonth = 118187 * i;
options.data.datasets.find(set => set.label === "Case").data.push(caseMonth);
const investMonth = 500000 + (20000 * i);
options.data.datasets.find(set => set.label === "Investment").data.push(investMonth);
const roiMonth = caseMonth - investMonth;
options.data.datasets.find(set => set.label === "ROI").data.push(roiMonth);
}
var ctx = document.getElementById('chartJSContainer').getContext('2d');
new Chart(ctx, options);
canvas { background-color : #eee;
}
<script src="https://cdnjs.cloudflare.com/ajax/libs/Chart.js/2.3.0/Chart.js"></script>
<body>
<canvas id="chartJSContainer" width="600" height="400"></canvas>
</body>

You can put null values on the chart data so one line can start after the others. For example if you want the investment line start at month 10, you can replace the the first ten investMonth values with null.
If understood correctly you still want to use the investMonth value in the roiMonth calculation so I created "investMonthValue" so only investment will get null if it is less than investmentStartMonth.
let investmentStartMonth = 10
for (let i = 1; i <= 60; i++) {
options.data.labels.push(i);
const caseMonth = 118187 * i;
options.data.datasets.find(set => set.label === "Case").data.push(caseMonth);
let investMonth = 500000 + (20000 * i);
let investMonthValue = i<investmentStartMonth?null:investMonth
options.data.datasets.find(set => set.label === "Investment").data.push(investMonthValue);
const roiMonth = caseMonth - investMonth;
options.data.datasets.find(set => set.label === "ROI").data.push(roiMonth);
}

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
},
{
label: 'de vsy',
backgroundColor: color(window.chartColors.blue).alpha(0.5).rgbString(),
borderColor: window.chartColors.blue,
data: dataMaker(15),
type: 'line',
pointRadius: 2,
fill: false,
lineTension: 0,
borderWidth: 2
}
],
},
options: {
animation: {
duration: 0
},
scales: {
xAxes: [{
type: 'time',
distribution: 'series',
offset: true,
time: {
unit: 'month',
displayFormats: {
month: 'MMM'
}
},
ticks: {
autoSkip: true,
autoSkipPadding: 75,
sampleSize: 100
},
}],
yAxes: [{
gridLines: {
drawBorder: false
}
}]
},
tooltips: {
intersect: false,
mode: 'index',
}
}
};
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.
If true, grid lines will be shifted to be between labels.
xAxes: [{
...
gridLines: {
offsetGridLines: true
}
In most cases, this produces the expected result. Unfortunately it doesn't work for time axes as documented in Chart.js issue #403. Thanks to Antti Hukkanen, there exists a workaround.
Please have a look at below runnable code snippet to see how it works.
function generateData() {
var unit = 'day';
function randomNumber(min, max) {
return Math.random() * (max - min) + min;
}
function randomPoint(date, lastClose) {
var open = randomNumber(lastClose * 0.95, lastClose * 1.05).toFixed(2);
var close = randomNumber(open * 0.95, open * 1.05).toFixed(2);
return {
t: date.valueOf(),
y: close
};
}
var date = moment().subtract(1, 'years');
var now = moment();
var data = [];
for (; data.length < 600 && date.isBefore(now); date = date.clone().add(1, unit).startOf(unit)) {
data.push(randomPoint(date, data.length > 0 ? data[data.length - 1].y : 30));
}
return data;
}
var TimeCenterScale = Chart.scaleService.getScaleConstructor('time').extend({
getPixelForTick: function(index) {
var ticks = this.getTicks();
if (index < 0 || index >= ticks.length) {
return null;
}
// Get the pixel value for the current tick.
var px = this.getPixelForOffset(ticks[index].value);
// Get the next tick's pixel value.
var nextPx = this.right;
var nextTick = ticks[index + 1];
if (nextTick) {
nextPx = this.getPixelForOffset(nextTick.value);
}
// Align the labels in the middle of the current and next tick.
return px + (nextPx - px) / 2;
},
});
// Register the scale type
var defaults = Chart.scaleService.getScaleDefaults('time');
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>
<canvas id="chart1" height="90"></canvas>

For chartJs v3 you can use offset property:
scales: {
x: {
grid: {
offset: true
}
},
...
}

attempting to destroy previous graph on canvas

I am creating multiple graphs on the same canvas but I am unable to successfully use the destroy() API to clean up the previous data.
HERE IS MY JS CODE FOR CREATING A CHART
const getCountryDataByMonth = async (country) => {
document.getElementById('casesGraphHeader').innerHTML = "Loading....";
const response = await fetch ('https://cors-anywhere.herokuapp.com/https://pomber.github.io/covid19/timeseries.json');
const data = await response.json();
const reports = await data[country];
var i;
var dateList = [];
var caseByDay = [];
var deathsByDay = [];
for(i = 0; i < reports.length; i++){
dateList.push(reports[i].date);
caseByDay.push(reports[i].confirmed);
deathsByDay.push(reports[i].deaths);
}
//GRAPH FOR TOTAL CASES
var casesOptions = {
type: 'bar',
data: {
labels: dateList,
datasets: [
{
label: 'Total Cases',
data: caseByDay,
backgroundColor: '#f49d12',
borderColor: '#f49d12',
fill: false,
borderWidth: 2
}
]
},
options: {
legend: {
labels: {
fontSize: 15
}
},
scales: {
yAxes: [{
ticks: {
reverse: false,
fontSize: 15
}
}],
xAxes: [{
ticks: {
fontSize: 15
}
}],
}
}
}
var totalCasesChart = document.getElementById('totalCasesContainer').getContext('2d');
new Chart(totalCasesChart, casesOptions);
document.getElementById('casesGraphHeader').innerHTML = "Total Cases for "+country;
//GRAPH FOR TOTAL Deaths
var deathOptions = {
type: 'bar',
data: {
labels: dateList,
datasets: [
{
label: 'Total Deaths',
data: deathsByDay,
backgroundColor: '#e84c3d',
borderColor: '#e84c3d',
fill: false,
borderWidth: 2
}
]
},
options: {
legend: {
labels: {
fontSize: 15
}
},
scales: {
yAxes: [{
ticks: {
reverse: false,
fontSize: 15
}
}],
xAxes: [{
ticks: {
fontSize: 15
}
}],
}
}
}
var totalCasesChart = document.getElementById('totalDeathsContainer').getContext('2d');
new Chart(totalDeathsContainer, deathOptions);
document.getElementById('deathsGraphHeader').innerHTML = "Total Deaths for "+country;
};
function renderChart(){
getCountryDataByMonth(document.getElementById('myInput').value);
}
function defaultChart() {
getCountryDataByMonth('US');
}
window.onload = defaultChart;
This is what I tried. I basically did
if(caseBar){
caseBar.destroy();
}
However, this does not work. In my FIDDLE you can try to type China first click to create the graph and then type Italy. Then HOVER over the Italy graph and you will see the stats from china appear on the graph.

Your code is riddle with issues, here is some of the stuff I see:
Look at what you are doing when you create the new charts:
var totalCasesChart = document.getElementById('totalCasesContainer').getContext('2d');
var caseBar = new Chart(totalCasesChart, casesOptions);
document.getElementById('casesGraphHeader').innerHTML = "Total Cases for " + country;
vs
var totalCasesChart = document.getElementById('totalDeathsContainer').getContext('2d');
new Chart(totalDeathsContainer, deathOptions);
document.getElementById('deathsGraphHeader').innerHTML = "Total Deaths for " + country;
You are calling the:
await fetch('https://cors-anywhere.herokuapp.com/https://pomber.github.io/...');
again and again when you should do it just once...
There are many variables that should be global to reduce what you do in getCountryDataByMonth, a perfect example are the totalCasesChart and caseBar
I made a few tweaks to your code here:
https://raw.githack.com/heldersepu/hs-scripts/master/HTML/chart_test.html

Update ChartJs chart using $scope in AngularJS

I'm having some issues when trying to update a chart's data using $scope.
I know there's a function to update charts myChart.update(); but I can't get to update the char when I put it in a $scope.
The following code gets the chart's data and then tries to update the chart. The problem comes at $scope.lineChart.update();. It looks like chartjs can't detect any changes.
The following code is executed after triggering a select, so the chart has an initial data and the following code just tries to update it.
This does not work: $scope.lineChart.update();
$scope.getLineChartMaxData().then(function () {
$scope.getLineChartMinData().then(function () {
$scope.lineChart.update();
});
});
The chart function:
$scope.fillLineChart = function () {
console.log("FILLING LINE CHART");
const brandProduct = 'rgba(0,181,233,0.5)'
const brandService = 'rgba(0,173,95,0.5)'
var data1 = $scope.lineChartMaxWeekData;
var data2 = $scope.lineChartMinWeekData;
var maxValue1 = Math.max.apply(null, data1)
var maxValue2 = Math.max.apply(null, data2)
var minValue1 = Math.min.apply(null, data1)
var minValue2 = Math.min.apply(null, data2)
var maxValue;
var minValue;
if (maxValue1 >= maxValue2) {
maxValue = maxValue1;
} else {
maxValue = maxValue2;
}
if (minValue1 >= minValue2) {
minValue = minValue2;
} else {
minValue = minValue1;
}
$scope.minValue = minValue;
$scope.maxValue = maxValue;
var ctx = document.getElementById("recent-rep-chart");
if (ctx) {
ctx.height = 250;
$scope.lineChart = new Chart(ctx, {
type: 'line',
data: {
labels: $scope.lineChartMaxWeekLabels,
datasets: [{
label: 'Valor',
backgroundColor: brandService,
borderColor: 'transparent',
pointHoverBackgroundColor: '#fff',
borderWidth: 0,
data: data1
},
{
label: 'My Second dataset',
backgroundColor: brandProduct,
borderColor: 'transparent',
pointHoverBackgroundColor: '#fff',
borderWidth: 0,
data: data2
}
]
},
options: {
maintainAspectRatio: true,
legend: {
display: false
},
responsive: true,
scales: {
xAxes: [{
gridLines: {
drawOnChartArea: true,
color: '#f2f2f2'
},
ticks: {
fontFamily: "Poppins",
fontSize: 12
}
}],
yAxes: [{
ticks: {
beginAtZero: true,
maxTicksLimit: 5,
stepSize: 50,
max: maxValue,
fontFamily: "Poppins",
fontSize: 12
},
gridLines: {
display: true,
color: '#f2f2f2'
}
}]
},
elements: {
point: {
radius: 0,
hitRadius: 10,
hoverRadius: 4,
hoverBorderWidth: 3
}
}
}
});
}
};
UPDATE: $scope.lineChart.destroy(); works well, but I don't want to destroy the chart and build it again because it is built with another sizes.