How to draw line within a defined x and y-axis on echart - echarts

I have a simple echart here with a simple horizontal line defined by the yAxis . My question is is there anyway I can confined the length of the line to a point on the xAxis? I want the line to end at '2017-10-18' instead of the end of the graph or '2017-10-20'
I tried specifying both x and y axis at the same time, but doesn't seem to be working. Any help will be appreciated.

You have 2 options :
Markline
series-line.markLine doc
This is what you used in your example, but replace markline data with that :
markLine: {
data: [[
{
coord: [0, 0.901],
},
{
coord: [4, 0.901]
}
]]
}
data is a list of marklines. To declare a line with specific [[x1, y1], [x2,y2]], you'll have to define a list of points within the list of marklines (that's why there are two brackets in a row).
Graphics
graphic.elements-line doc
Otherwise graphics gives more freedom to draw anything on the graph.
graphic: {
elements: [
{
type: 'group',
left: 'center',
top: 'center',
children: [
{
type: 'line',
x: 20,
shape: {
x1: -250,
y1: -100,
x2: 10,
y2: 40,
},
}
]
}
]
}
But x1,y1,x2 and y2 coordinates are in pixel. If you want it to use the series coordinates, you can use convertToPixel()
myChart.convertToPixel({seriesIndex: 0}, [0,0.901])
Result
In red : markline and in black : graphics
Code

Related

Get pixel coordinates of point in stacked series

In order to make my own markPoint div (since I cannot get Echarts markPoints to show up), I need to get the x,y pixel coordinates of a visual point on a stacked line chart where one series hits a 0 value. But because it is stacked, that 0 point isn't at the bottom of the chart, but somewhere higher sitting on top of other series lower in the stacking order. the echartsInstance.convertToPixel function is responding back with the y pixel coordinate at the bottom of the chart, where absolute 0 would be, but that's not where the series is. It's higher up, even with a 0 value, due to stacking.
Is there anyway, maybe through getModel() or getZr() to find out what the pixel coordinates are for a series (where it actually appears visually after stacking) at a given set of its own x,y values?
OK, let's imagine that you have a bar chart and you want to place the markPoint on the top of second bar, drawing the chart:
var myChart = echarts.init(document.getElementById('main'));
var option = {
xAxis: {
data: ["A", "B", "C"]
},
yAxis: {},
series: [{
name: 'Series1',
type: 'bar',
data: [5, 20, 36],
}]
}
myChart.setOption(option);
Then you should define the markPoint in series config:
// ...
markPoint: {
symbol: 'circle',
symbolSize: 10,
itemStyle: { color: 'black' },
data:[{
// here you defined: x = 'B' and y = '20'
coord: ['B', 20]
}]
}
// ...
Here you can find the full example.
Next. You want to place the div point with pixel coordinates depending on the size of bar. Here you convert the pixel coordinates into Echarts scale:
var [chartX, chartY] = myChart.convertToPixel({ seriesIndex: 0 }, [x, y]);
You need function to draw point on page:
function Point(opts){
var { x,y } = opts;
var canvas = document.getElementById('main');
var point = document.createElement('div');
point.classList.add('point');
var [chartX, chartY] = myChart.convertToPixel({ seriesIndex: 0 }, [x, y]);
point.style.left = chartX + 'px';
point.style.top = chartY + 'px';
return canvas.insertAdjacentElement('afterbegin', point);
}
and then call it:
var p1 = new Point({ x: 'B', y: 20 });
It's all. See full example.

How to make Echarts areaStyle fill whole polar?

I'm working with line-polar eCharts on Angular, and I ran into a problem with areaStyle. I want it to fill the whole area from the line to the outer most circle with the yellow color, but eCharts left out a little bit of empty space. I tried creating a shadowBlur and offsetX, Y it to the blank area, but the color is not the same. Is there a property of areaStyle I'm missing, or is there a library to fix this?
series = [{
coordinateSystem: 'polar',
name: this.legends[1],
type: 'line',
color: '#D9B100',
data: this.datasetCylinder.data,
smooth: true,
showSymbol: false,
lineStyle: {
show: true,
width: 3,
shadowBlur: 10,
shadowColor: 'gold'
},
areaStyle: {
color: 'gold',
origin: 'end',
opacity: 0.1
}
}]
A simple solution would be to add more points in between, but then chart yellow line might not have the correct form. Any suggestion is appreciated.
There is no easy solution but you can try to find it:
Draw the area outside the circle boundaries and then cut the excess with VisualMap.
Cut area in already filled circle by VisualMap with pieces.
Use custom series and draw all with polygons.

How to draw a circle layer on a scatter chart using Echarts

How to draw something like the below screenshot in Echarts?
With ECharts, I can easily draw scatter and axes, include zooming and panning features. However, when I need to draw a new layer on top of scatter, things getting messy. I tried using custom series of e-chart, however, its api and documentation is hard to understand, Besides, its zooming function works weird on multiple series.
You can create the circle by adding a customized data item to your scatter series.
Here's a sample option:
option = {
xAxis: {
max: 12
},
yAxis: {
max: 12
},
series: {
type: 'scatter',
symbolSize: 20,
data: [
[6.0, 8.04],
[8.0, 6.95],
[3.5, 8.81],
[5.0, 8.33],
[6.0, 7.24],
[4.0, 4.26],
[8.0, 7.84],
[7.0, 4.82],
[5.0, 5.68],
{
value: [6, 6],
symbolSize: 400,
itemStyle: {
color: 'rgba(1,1,1,0)',
borderColor: '#00f',
borderWidth: 4
}
}
]
}
};
...which should produce this output:
echarts scatter series with enclosing circle
See https://echarts.apache.org/en/option.html#series-scatter.data and scroll down a bit for more information on customized data items.

Mapbox - Style property according to zoom and property

I'd like to style points on my map as follows:
'circle-radius': {
property: 'pixelRadius',
stops: [
[0, 0],
[20, 'pixelRadius'],
],
base: 2,
}
The use case is similar to Drawing a circle with the radius in miles/meters with Mapbox GL JS
Except that in my properties map I have computed the pixel radius so that each point in the FeatureCollection has its own radius.
Can this be done? All of the examples Ive seen with stops have a hard coded value for the 2nd array element.
Try this:
'circle-radius': [
"interpolate",
["exponential", 2],
["zoom"],
0, 0,
20, ['get', 'pixelRadius']
],
So here it is using expression (https://www.mapbox.com/mapbox-gl-js/style-spec/#expressions-get) instead of function.

Highcharts - navigation by 3rd element in series 'hidden' in plot

I have some info which is in this format (speed, frequency, date). What happens is that I need to plot this chart with speed x frequency, but I want to allow the users to use the navigation filtering by the date, which is not appearing on the chart.
Also, I have some info which is not built dynamically, which is the limits of speed x frequency. This info will be fixed as reference points on the plot. So, when I filter the plot info (not the limits), it must always display these limit plots.
You can have an idea by this chart, the area plots show the limits for the points (speed, frequency). Then, I would add points of speed x frequency (x date), and filter then by date.
Can you guys give me some advice on this?
here is a JSFIDDLE
JSFIDDLE
data: [
[0, 20, here is a date], [10, 20,here is a date],
[50, 39.9994, here is a date], [100,49.7494, here is a date]
],
Guys, notice that every element of the array in the series has 3 elements [a, b, c], suppose the third one (c) is a DATE and not a random number as it is right now. I want to be able to use the commented the navigator code to filter this series by this C element, which doesn't in fact appear on the chart you see, it is a hidden element, just to filter the data.
There will be a little tricky, if you want to have a navigator in the same chart. Navigator works only with datetime data and it must be connected with the axis from the main chart.
So, you have data in that format:
var points = [
[5, 9, Date.UTC(2016, 1, 0)],
[65, 6, Date.UTC(2016, 1, 1)],
...
You need two x axes - one which represents the data and the other which is connected to the navigator. The second axis must be visible to work with the navigator and must be connected with the datetime data.
So now, except two x axes, you need two series - one with the actual data, and the other consists of [date, y] values from the first series. The additional data will be visible in the navigator - note, that in the navigator you cannot use scatter series - so it will be converted to line series - to happen it without errors, your data should be sorted by date.
series: [{
id: 'main-series',
data: points.map(function(point) {
return [point[0], point[1], point[2], point[1]]
}),
showInNavigator: false,
xAxis: 1,
keys: ['x', 'y', 'date', 'holdY'] //holdY is for easier hiding points
}, {
xAxis: 0,
data: points.map(function(point) {
return [point[2], point[1]];
}),
showInNavigator: true,
enableMouseTracking: false,
color: 'transparent',
showInLegend: false
}],
xAxis: [{
minRange: 1000 * 3600 * 24,
type: 'datetime',
tickLength: 0,
tickLength: 0,
labels: {
enabled: false
},
}, {
type: 'linear'
}],
The last thing you need a callback which will hide/show points after the extremes in the navigator are set. Hiding/showing depends on the third point's property which is date. There is no directly API to hide/show specific points (except pie), but it can be achieved by setting point's value to null (that is why I preserved the real y in holdY).
events: {
afterSetExtremes: function(e) {
var points = this.chart.get('main-series').points;
points.forEach(function(point) {
point.update({
y: e.min <= point.date && point.date <= e.max ? point.holdY : null
}, false, false);
});
this.chart.redraw();
}
}
example: https://jsfiddle.net/3wuwdonn/1/
I would consider using a navigator as a separate chart, then you wouldn't need the second x axis and series in the main chart and you wouldn't need to make them look invisible.
example with a navigator only chart here: http://jsfiddle.net/f7Y9p/