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I want to draw a reference line in the time series chart. I tried to use two x axis and two y axis so I have like two graphs in one. the one would show time scale line and the other one would show linear line (reference line).
image example of what I want it to look like :
I tried in fiddle but its like the two X axis are connected and not scaling separately:
var data = {
labels: [],
datasets: [{
fill: 'none',
label: 'signal1',
backgroundColor: 'rgba(75,192,192,0.4)',
pointRadius: 5,
pointHoverRadius: 7,
borderColor: 'rgba(75,192,192,1)',
borderWidth: 1,
lineTension: 0,
xAxisID: 'xAxis1',
yAxisID: 'yAxis1',
data: [{
x: '2016-07-17',
y: 44
},
{
x: '2016-07-19',
y: 50
},
{
x: '2016-07-22',
y: 84
},
],
}, {
fill: 'none',
label: 'signal2',
lineTension: 0,
xAxisID: 'xAxis2',
yAxisID: 'yAxis2',
data: [{
x: 0,
y: 55
},
{
x: 1,
y: 55
},
]
}],
};
var option = {
scales: {
yAxes: [{
id: 'yAxis1',
offset: true,
gridLines: {
color: 'rgba(151, 151, 151, 0.2)',
display: true,
zeroLineColor: '#979797',
zeroLineWidth: 1,
tickMarkLength: 15,
drawBorder: true,
},
ticks: {
beginAtZero: false,
padding: 5,
fontSize: 12,
fontColor: '#222222',
},
}, {
id: 'yAxis2',
gridLines: {
color: 'rgba(151, 151, 151, 0.2)',
display: false,
drawBorder: false,
},
ticks: {
beginAtZero: false,
},
}],
xAxes: [{
id: 'xAxis1',
offset: true,
bounds: 'data',
type: 'time',
distribution: 'linear',
time: {
unit: 'day',
displayFormats: {
day: 'D.M.YYYY',
},
},
gridLines: {
display: true,
color: 'rgba(151, 151, 151, 0.2)',
zeroLineColor: '#979797',
zeroLineWidth: 1,
tickMarkLength: 5,
drawBorder: true,
},
ticks: {
source: 'auto',
autoSkip: true,
autoSkipPadding: 30,
maxRotation: 0,
padding: 2,
fontSize: 12,
fontColor: '#222222',
},
}, {
id: 'xAxis2',
type:"linear",
gridLines: {
display: false,
drawBorder: false,
},
}]
}
};
https://jsfiddle.net/2gyk9v5e/15/
This can be done with the Plugin Core API. The API offers different hooks that may be used for executing custom code. In your case, you can use the afterDraw hook to draw the desired lines directly on the canvas using CanvasRenderingContext2D.
plugins: [{
afterDraw: chart => {
var ctx = chart.chart.ctx;
var xAxis = chart.scales['x-axis-0'];
var yAxis = chart.scales['y-axis-0'];
ctx.save();
chart.data.datasets[0].refLines.forEach(r => {
var y = yAxis.getPixelForValue(r.y);
ctx.strokeStyle = r.color;
ctx.beginPath();
ctx.moveTo(xAxis.left, y);
ctx.lineTo(xAxis.right, y);
ctx.stroke();
});
ctx.restore();
}
}],
Above code assumes that the reference lines are defined inside your dataset through the following definition.
refLines: [
{ y: 45, color: '#0be059' },
{ y: 49, color: '#fc3503' }
]
Please take a look at your amended code and see how it works.
new Chart('canvas', {
type: 'line',
plugins: [{
afterDraw: chart => {
var ctx = chart.chart.ctx;
var xAxis = chart.scales['x-axis-0'];
var yAxis = chart.scales['y-axis-0'];
ctx.save();
chart.data.datasets[0].refLines.forEach(r => {
var y = yAxis.getPixelForValue(r.y);
ctx.strokeStyle = r.color;
ctx.beginPath();
ctx.moveTo(xAxis.left, y);
ctx.lineTo(xAxis.right, y);
ctx.stroke();
});
ctx.restore();
}
}],
data: {
datasets: [{
fill: false,
label: 'signal1',
backgroundColor: 'rgba(75,192,192,0.4)',
pointRadius: 5,
pointHoverRadius: 7,
borderColor: 'rgba(75,192,192,1)',
borderWidth: 1,
lineTension: 0,
data: [
{ x: '2016-07-14', y: 44 },
{ x: '2016-07-15', y: 52 },
{ x: '2016-07-16', y: 45 },
{ x: '2016-07-17', y: 47 },
{ x: '2016-07-18', y: 35 },
{ x: '2016-07-19', y: 46 },
{ x: '2016-07-20', y: 50 },
{ x: '2016-07-21', y: 44 }
],
refLines: [
{ y: 45, color: '#0be059' },
{ y: 49, color: '#fc3503' }
]
}]
},
options: {
scales: {
yAxes: [{
gridLines: {
color: 'rgba(151, 151, 151, 0.2)',
display: false,
drawBorder: false
}
}],
xAxes: [{
offset: true,
bounds: 'data',
type: 'time',
time: {
unit: 'day',
displayFormats: {
day: 'D.M.YYYY',
}
},
gridLines: {
color: 'rgba(151, 151, 151, 0.2)',
zeroLineColor: '#979797',
zeroLineWidth: 1,
tickMarkLength: 5,
drawBorder: true
}
}]
}
}
});
<script src="https://cdnjs.cloudflare.com/ajax/libs/Chart.js/2.9.4/Chart.bundle.min.js"></script>
<canvas id="canvas" height="80"></canvas>
I want to plot the variance of multiple signals in a chart (or basically fillup the space between an upper and a lower signal).
Is it possible to create such kind of charts?
I saw the confidence-band example (https://echarts.apache.org/examples/en/editor.html?c=confidence-band) , however this seems to work only for one signal in a chart.
Another solution would be to draw thousands of small rectangles using markArea around the signals but this slows down the performance of the chart (e.g. when scrolling the x-axisis) and doesnt look very smooth.
As I know the common practice in Echarts community draw usual chart type (bar, line, ...) with series (read docs) and write visual logic by custom series for unique. Also Echarts has some API methods (undocumented) like registerVisual, registerLayout that can be used for redefine layouts, computation and so on.
For described task you need to use custom series for calculate bands coordinates. It's not very simple because (it seems to me) mandatory requirements with confidence band is rare.
About performance. Echarts by default use Canvas for render visual parts. Usually Canvas has no many parts in HTML for display chart, it's just imageData rendered by browser and it almost doesn't matter how many data point need to display. In other words, we see PNG, and not a lot of div, svg, g and others layers with geometric primitives as in SVG but heavy computation complex business logic may affect the responsiveness of UI as in other charts.
Below example how would I implement this feature. I'm not sure that's the right way but it work and can be tuned.
var dates = ['2020-01-03','2020-01-31','2020-02-17','2020-02-18','2020-03-13','2020-04-10','2020-05-01','2020-05-19','2020-05-22','2020-05-25'];
var sensor1 = [0.6482086334797242, 0.9121368038482911, 0.3205730196548609, 0.8712238348969002, 0.4487714576177558, 0.9895025457815625, 0.0415490306934774, 0.1592908349676395, 0.5356690594518069, 0.9949108727912939];
var sensor2 = [0.8278430459565170, 0.5700757488718124, 0.9803575576802187, 0.0770264671179814,0.2843735619252158,0.8140209568127250,0.6055633547296827,0.9554255125528607,0.1703504100638565,0.5653245914197297];
// Calculate fake bands coordinates
function calcContourCoords(seriesData, ctx){
var addNoise = idx => Math.round(Math.random() * 8 * idx);
var pixelCoords = seriesData.map((dataPoint, idx) => {
return [
ctx.convertToPixel({ xAxisIndex: 0 }, idx) + addNoise(idx),
ctx.convertToPixel({ yAxisIndex: 0 }, dataPoint) + addNoise(idx)
]
});
var polyfilltype = ClipperLib.PolyFillType.pftEvenOdd;
var linePath = new ClipperLib.Path();
var delta = 15;
var scale = 1;
for (var i = 0; i < pixelCoords.length; i++){
var point = new ClipperLib.IntPoint(...pixelCoords[i]);
linePath.push(point);
}
var co = new ClipperLib.ClipperOffset(1.0, 0.25);
co.AddPath(linePath, ClipperLib.JoinType.jtRound, ClipperLib.EndType.etOpenSquare);
co.Execute(linePath, delta * scale);
return co.m_destPoly.map(c => [c.X, c.Y])
}
// Render visual by calculated coords
function renderItem(params, api){
// Prevent multiple call
if (params.context.rendered) return;
params.context.rendered = true;
// Get stored in series data for band
var series = myChart.getModel().getSeriesByName(params.seriesName)[0];
var seriesData = series.get('data');
// Calculate band coordinates for series
var bandCoords = calcContourCoords(seriesData, myChart);
// Draw band
return {
type: 'polygon',
shape: {
points: echarts.graphic.clipPointsByRect(bandCoords, {
x: params.coordSys.x,
y: params.coordSys.y,
width: params.coordSys.width,
height: params.coordSys.height
})
},
style: api.style({
fill: series.option.itemStyle.color
})
};
}
// =============
var option = {
tooltip: {},
legend: {
data:['Label']
},
xAxis: [
{ name: 'x0', data: dates, boundaryGap: true },
{ name: 'x1', data: dates, boundaryGap: true, show: false },
],
yAxis: [
{ name: 'y0' },
{ name: 'y1', show: false },
],
series: [
// First line
{
name: 'Sensor1',
type: 'line',
data: sensor1,
itemStyle: { color: 'rgba(69, 170, 242, 1)' },
yAxisIndex: 0,
xAxisIndex: 0,
},
{
name: 'BandSensor1',
type: 'custom',
data: sensor1,
itemStyle: { color: 'rgba(69, 170, 242, 0.2)' },
renderItem: renderItem,
yAxisIndex: 0,
xAxisIndex: 0,
},
// Second line
{
name: 'Sensor2',
type: 'line',
data: sensor2,
itemStyle: { color: 'rgba(253, 151, 68, 1)' },
yAxisIndex: 1,
xAxisIndex: 1,
},
{
name: 'BandSensor2',
type: 'custom',
data: sensor2,
itemStyle: { color: 'rgba(253, 151, 68, 0.2)' },
renderItem: renderItem,
yAxisIndex: 1,
xAxisIndex: 1,
},
]
};
var myChart = echarts.init(document.getElementById('main'));
myChart.setOption(option);
<script src="https://cdn.jsdelivr.net/npm/clipper-lib#6.4.2/clipper.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/echarts/4.7.0/echarts.min.js"></script>
<div id="main" style="width: 800px;height:600px;"></div>
Improved version of #Sergey Fedorov- this solution takes into account min,max values or. dynamic border thicness of the band
var dates = ['2020-01-03', '2020-01-31', '2020-02-17', '2020-02-18', '2020-03-13', '2020-04-10', '2020-05-01', '2020-05-19', '2020-05-22', '2020-05-25', '2020-05-27'];
const data_raw1 = [
{ min: -5, mean: 0, max: 0 },
{ min: 1, mean: 2, max: 5 },
{ min: 2, mean: 4, max: 6 },
{ min: 4, mean: 5, max: 8 },
{ min: 7, mean: 11, max: 14 },
{ min: 11, mean: 15, max: 17 },
{ min: 6, mean: 8, max: 8.5 },
{ min: -1, mean: 5, max: 6 },
{ min: 4, mean: 9, max: 12 },
{ min: 14, mean: 18, max: 22 },
{ min: 18, mean: 20, max: 21 },
];
const data_raw2 = [
{ min: 10, mean: 15, max: 20 },
{ min: 12, mean: 25, max: 30 },
{ min: 22, mean: 26, max: 32 },
{ min: 30, mean: 31, max: 45 },
{ min: 47, mean: 49, max: 50 },
{ min: 30, mean: 32, max: 41 },
{ min: 34, mean: 36, max: 38 },
{ min: 40, mean: 42, max: 45 },
{ min: 47, mean: 49, max: 56 },
{ min: 60, mean: 68, max: 70 },
{ min: 75, mean: 80, max: 85 },
];
const data_raw3 = data_raw2.map(d => ({ min: d.min * 1.2 + 10, mean: d.mean * 1.4 + 11, max: d.max * 1.5 + 12 }))
function calcContourCoords(seriesData, ctx) {
console.log("seriesData=", seriesData);
const pixelCoords = []
for (let i = 0; i < seriesData.length; i++) {
console.log(i, seriesData[i]);
pixelCoords.push([
ctx.convertToPixel({ xAxisIndex: 0 }, i),
ctx.convertToPixel({ yAxisIndex: 0 }, seriesData[i].max)
]);
}
console.log("\n")
for (let i = seriesData.length - 1; i >= 0; i--) {
console.log(i, seriesData[i]);
pixelCoords.push([
ctx.convertToPixel({ xAxisIndex: 0 }, i),
ctx.convertToPixel({ yAxisIndex: 0 }, seriesData[i].min)
]);
if (i == 0) {
pixelCoords.push([
ctx.convertToPixel({ xAxisIndex: 0 }, i),
ctx.convertToPixel({ yAxisIndex: 0 }, seriesData[i].max)
]);
}
}
var linePath = new ClipperLib.Path();
var delta = 10;
var scale = 1;
for (var i = 0; i < pixelCoords.length; i++) {
var point = new ClipperLib.IntPoint(...pixelCoords[i]);
linePath.push(point);
}
var co = new ClipperLib.ClipperOffset(1.0, 0.25);
co.AddPath(linePath, ClipperLib.JoinType.jtRound, ClipperLib.EndType.etClosedPolygon);
co.Execute(linePath, delta * scale);
return co.m_destPoly.map(c => [c.X, c.Y])
}
// Render visual by calculated coords
function renderItem(params, api) {
// Prevent multiple call
if (params.context.rendered) return;
params.context.rendered = true;
// Get stored in series data for band
var series = myChart.getModel().getSeriesByName(params.seriesName)[0];
var seriesData = series.get('data');
// Calculate band coordinates for series
var bandCoords = calcContourCoords(seriesData, myChart);
// Draw band
return {
type: 'polygon',
shape: {
points: echarts.graphic.clipPointsByRect(bandCoords, {
x: params.coordSys.x,
y: params.coordSys.y,
width: params.coordSys.width,
height: params.coordSys.height
})
},
style: api.style({
fill: series.option.itemStyle.color
})
};
}
// =============
var option = {
tooltip: {},
legend: {
data: ['Label']
},
xAxis: [
{ name: 'x0', data: dates, boundaryGap: true },
{ name: 'x1', data: dates, boundaryGap: true, show: false },
],
yAxis: [
{ name: 'y0' },
{ name: 'y1', show: false },
],
series: [
// First line
{
name: 'Sensor1',
type: 'line',
data: data_raw1.map(d => d.mean),
itemStyle: { color: 'rgba(69, 170, 242, 1)' },
yAxisIndex: 0,
xAxisIndex: 0,
itemStyle: { color: 'red' },
},
{
name: 'BandSensor1',
type: 'custom',
data: data_raw1,
itemStyle: { color: 'rgba(69, 170, 242, 0.2)' },
renderItem: renderItem,
yAxisIndex: 0,
xAxisIndex: 0,
itemStyle: { color: 'red', opacity: 0.1 },
},
{
name: 'Sensor2',
type: 'line',
data: data_raw2.map(d => d.mean),
itemStyle: { color: 'rgba(69, 170, 242, 1)' },
yAxisIndex: 0,
xAxisIndex: 0,
itemStyle: { color: 'blue' },
},
{
name: 'BandSensor2',
type: 'custom',
data: data_raw2,
itemStyle: { color: 'rgba(69, 170, 242, 0.2)' },
renderItem: renderItem,
yAxisIndex: 0,
xAxisIndex: 0,
itemStyle: { color: 'blue', opacity: 0.1 },
},
{
name: 'Sensor3',
type: 'line',
data: data_raw3.map(d => d.mean),
itemStyle: { color: 'rgba(69, 170, 242, 1)' },
yAxisIndex: 0,
xAxisIndex: 0,
itemStyle: { color: 'green' },
},
{
name: 'BandSensor3',
type: 'custom',
data: data_raw3,
itemStyle: { color: 'rgba(69, 170, 242, 0.2)' },
renderItem: renderItem,
yAxisIndex: 0,
xAxisIndex: 0,
itemStyle: { color: 'green', opacity: 0.1 },
},
]
};
var myChart = echarts.init(document.getElementById('chart'));
myChart.setOption(option);
I am trying to create a line chart that presents score level from 1-100.
Line is static and needs to be curved
but the dot on the chart is dynamic value and by that it changes its location along the existing line.
First I was thinking to add additional data that represents only the dot itself, but Y(height) is unknown.
Second attempt led me to create a second line that crosses / intersects the first one in hope of finding intersection point and making it a dot.
Unfortunately, I couldn't find a way to locate intersection.
This is expected result.
new Chart(
document.getElementById('lineChart'), {
type: 'line',
data: {
datasets: [
{
data: [
{
x: 70, y: 0,
},
{
x: 70, y: 100,
}],
fill: false,
borderColor: 'red',
showLine:true,
},
{
data: [
{
x: 0, y: 2,
},
{
x: 25, y: 10,
},
{
x: 50, y: 50,
},
{
x: 80, y: 90,
},
{
x: 100, y: 98,
}],
startWithZero: true,
fill: false,
lineTension: 0.3,
borderColor: 'blue',
}
]
},
options: {
bezierCurve : true,
lineTension: 0.3,
tooltips: {
mode: 'intersect'
},
scales: {
xAxes: [{
type: 'linear',
ticks: {
min: 0, //minimum tick
max: 100, //maximum tick
},
}],
yAxes: [{
ticks: {
bezierCurve : true,
min: 0, //minimum tick
max: 100, //maximum tick
},
bezierCurve : true,
type: 'linear',
lineTension: 0.3,
scaleLabel: {
lineTension: 0.1,
display: true,
}
}]
}
}
})
<script src="https://cdnjs.cloudflare.com/ajax/libs/Chart.js/2.8.0/Chart.min.js"></script>
<body>
<div style="width: 750px; height: 250px; margin: 0 auto;">
<canvas style="width: 750px; height: 250px" id="lineChart"></canvas>
</div>
</body>
You can check snippet in order to see example and how far I got.
Can you try to create dynamic values
const lineData = [
{ x: 0, y: 2 },
{ x: 10, y: 3 },
{ x: 20, y: 10 },
{ x: 30, y: 20 },
{ x: 40, y: 35 },
{ x: 50, y: 50 },
{ x: 60, y: 65 },
{ x: 70, y: 80 },
{ x: 80, y: 90 },
{ x: 90, y: 97 },
{ x: 100, y: 98 },
];
const xValue = 70;
let key = Math.floor(xValue / 10);
let diff = (lineData[key + 1].y - lineData[key].y) / 10;
let toAdd = (xValue - lineData[key].x) * diff;
const yValue = lineData[key].y + toAdd;
And include dynamic values in chartJs code
new Chart(
document.getElementById('lineChart'), {
type: 'line',
data: {
datasets: [
{
data: lineData,
startWithZero: true,
fill: false,
lineTension: 0.3,
borderColor: 'blue',
}
]
},
options: {
bezierCurve : true,
lineTension: 0.3,
tooltips: {
mode: 'intersect'
},
scales: {
xAxes: [{
type: 'linear',
ticks: {
min: 0, //minimum tick
max: 100, //maximum tick
},
}],
yAxes: [{
ticks: {
bezierCurve : true,
min: 0, //minimum tick
max: 100, //maximum tick
},
bezierCurve : true,
type: 'linear',
lineTension: 0.3,
scaleLabel: {
lineTension: 0.1,
display: true,
}
}]
}
}
})
const lineData = [
{ x: 0, y: 2 },
{ x: 10, y: 3 },
{ x: 20, y: 10 },
{ x: 30, y: 20 },
{ x: 40, y: 35 },
{ x: 50, y: 50 },
{ x: 60, y: 65 },
{ x: 70, y: 80 },
{ x: 80, y: 90 },
{ x: 90, y: 97 },
{ x: 100, y: 98 },
];
const xValue = 70;
let key = Math.floor(xValue / 10);
let diff = (lineData[key + 1].y - lineData[key].y) / 10;
let toAdd = (xValue - lineData[key].x) * diff;
const yValue = lineData[key].y + toAdd;
new Chart(
document.getElementById('lineChart'), {
type: 'line',
data: {
datasets: [
{
data: lineData,
startWithZero: true,
fill: false,
lineTension: 0.3,
borderColor: 'blue',
}
]
},
options: {
bezierCurve : true,
lineTension: 0.3,
tooltips: {
mode: 'intersect'
},
scales: {
xAxes: [{
type: 'linear',
ticks: {
min: 0, //minimum tick
max: 100, //maximum tick
},
}],
yAxes: [{
ticks: {
bezierCurve : true,
min: 0, //minimum tick
max: 100, //maximum tick
},
bezierCurve : true,
type: 'linear',
lineTension: 0.3,
scaleLabel: {
lineTension: 0.1,
display: true,
}
}]
}
}
})
<script src="https://cdnjs.cloudflare.com/ajax/libs/Chart.js/2.8.0/Chart.min.js"></script>
<body>
<div style="width: 750px; height: 250px; margin: 0 auto;">
<canvas style="width: 750px; height: 250px" id="lineChart"></canvas>
</div>
</body>
I'm building a vertical gauge and am having problems applying a custom image in place of the default marker.
Although the image renders, it's placement is off. I can't seem to get it to point exactly where the marker is positioned and I'm not sure if applying a static offset value to the 'y' attribute is the right approach.
Here's a fiddle.
var chart = new Highcharts.Chart({
chart: {
renderTo: 'container',
type: 'column',
marginBottom: 25,
marginTop: 70,
marginLeft: 65,
marginRight: 10,
},
xAxis: {
categories: ['One'],
lineColor: 'white',
labels: {
enabled: false
},
tickLength: 0,
min: 0,
max: 2
},
plotOptions: {
column: {
stacking: 'normal',
animation: false,
borderWidth: 0,
}
},
yAxis: {
min: 0,
max: 9026,
tickInterval: 9026,
tickLength: 0,
tickWidth: 0,
tickColor: '#C0C0C0',
gridLineColor: '#C0C0C0',
gridLineWidth: 0,
minorTickInterval: 25,
minorTickWidth: 0,
minorTickLength: 0,
minorGridLineWidth: 0,
title: null,
labels: {
formatter: function () {
if (this.isFirst || this.isLast) {
return this.value;
}
},
x: 0
},
},
legend: {
enabled: false
},
series: [
{
data: [4513],
color: {
linearGradient: { x1: 0, x2: 0, y1: 0, y2: 1 },
stops: [
[0, 'red'],
[1, 'orange']
]
}
},
{
data: [4513],
color: {
linearGradient: { x1: 0, x2: 0, y1: 0, y2: 1 },
stops: [
[0, 'orange'],
[1, 'green']
]
}
},
{
type: 'scatter',
data: [3120],
marker: {
enabled: true,
symbol: 'circle'
},
dataLabels: {
useHTML: true,
formatter: function () {
return '<img width="40px" height="40px" src="http://icongal.com/gallery/image/57585/small_arrow_black_monotone_left.png" />'
},
enabled: true,
align: 'right',
x: -3,
y: 2,
overflow: "justify"
}
}
]
});
<script src="https://code.highcharts.com/highcharts.js"></script>
<div id="container" style="width: 178px; height: 242px;"></div>
Would appreciate any help, thanks!
You should adjust the image position via x, y properties.
x: 0,
y: 30,
example: https://jsfiddle.net/ptezqnbf/1/
or even better, use renderer.image and control the position directly.
function renderImage() {
var chart = this,
point = chart.get('point'),
imgWidth = 40,
imgHeight = 40;
if (!chart.dataLabelImg) {
chart.dataLabelImg = this.renderer.image('http://icongal.com/gallery/image/57585/small_arrow_black_monotone_left.png', -1000, -1000, imgWidth, imgHeight).add(point.series.dataLabelsGroup);
}
chart.dataLabelImg.attr({
x: point.graphic.x + (imgWidth - 15) / 2,
y: point.graphic.y - (imgHeight - 10) / 2
});
example: https://jsfiddle.net/tpp1gdau/1/
I'm using highcharts and i'd like to show a big gauge(500x500px).
Resizing the gauge was quite easy, but the small block with the value in it doesn't resize. How can I make that small block bigger?
Thanks for the help!
jsFiddle: http://jsfiddle.net/AVd8k/
$(function () {
$('#container').highcharts({
chart: {
type: 'gauge',
plotBackgroundColor: null,
plotBackgroundImage: null,
plotBorderWidth: 0,
plotShadow: false,
width: 500,
height: 500
},
title: {
text: 'Speedometer'
},
pane: {
startAngle: -150,
endAngle: 150,
background: [{
backgroundColor: {
linearGradient: { x1: 0, y1: 0, x2: 0, y2: 1 },
stops: [
[0, '#FFF'],
[1, '#333']
]
},
borderWidth: 0,
outerRadius: '109%'
}, {
backgroundColor: {
linearGradient: { x1: 0, y1: 0, x2: 0, y2: 1 },
stops: [
[0, '#333'],
[1, '#FFF']
]
},
borderWidth: 1,
outerRadius: '107%'
}, {
// default background
}, {
backgroundColor: '#DDD',
borderWidth: 0,
outerRadius: '105%',
innerRadius: '103%'
}]
},
// the value axis
yAxis: {
min: 0,
max: 200,
minorTickInterval: 'auto',
minorTickWidth: 1,
minorTickLength: 10,
minorTickPosition: 'inside',
minorTickColor: '#666',
tickPixelInterval: 30,
tickWidth: 2,
tickPosition: 'inside',
tickLength: 10,
tickColor: '#666',
labels: {
step: 2,
rotation: 'auto'
},
title: {
text: 'km/h'
},
plotBands: [{
from: 0,
to: 120,
color: '#55BF3B' // green
}, {
from: 120,
to: 160,
color: '#DDDF0D' // yellow
}, {
from: 160,
to: 200,
color: '#DF5353' // red
}]
},
series: [{
name: 'Speed',
data: [80],
tooltip: {
valueSuffix: ' km/h'
}
}]
},
// Add some life
function (chart) {
if (!chart.renderer.forExport) {
setInterval(function () {
var point = chart.series[0].points[0],
newVal,
inc = Math.round((Math.random() - 0.5) * 20);
newVal = point.y + inc;
if (newVal < 0 || newVal > 200) {
newVal = point.y - inc;
}
point.update(newVal);
}, 3000);
}
});
});
try this by replacing series (whole object) with:
series: [{
name: 'Speed',
data: [80],
tooltip: {
valueSuffix: ' km/h'
},
dataLabels: {
enabled: true,
style: {
//fontWeight:'bold',
fontSize: '22px'
}
}
}]
Proof: http://jsfiddle.net/nmQfE/
Of course, you can adjust the font size as you want
It looks like the property you are after is:
plotOptions.gauge.dataLabels.style.fontSize
http://api.highcharts.com/highcharts#plotOptions.gauge.dataLabels.style
Try adding something like this to the options:
plotOptions: {
gauge: {
dataLabels: {
style: {
fontSize: '60px'
}
}
}
}
You may need to reposition it using the x and y properties.