Customize the chart drawing function.
Chart object. object
Chart(options)
The options parameter is the chart configuration. The Chart() function parameter options is a JSON serializable HighStocks parameter for Highcharts.StockChart. An additional __isStock attribute is added over the native parameter, and if __isStock:false is specified, it is displayed as a normal chart. If the __isStock attribute is set to a false value e.g. false, i.e. the chart used is a Highcharts chart. If the __isStock attribute is set to a true value e.g. true, i.e. the chart used is a Highstocks chart (by default __isStock is true e.g. true). You can query the HighStocks chart library.
options
true
object, object array
function main() {
var cfgA = {
extension: {
layout: 'single', // No grouping, display separately, default to group 'group'
height: 300, // Specify the height
},
title: {
text: 'handicap chart'
},
xAxis: {
type: 'datetime'
},
series: [{
name: 'buy one',
data: [],
}, {
name: 'sell one',
data: [],
}]
}
var cfgB = {
title: {
text: 'spread chart'
},
xAxis: {
type: 'datetime'
},
series: [{
name: 'spread',
type: 'column',
data: [],
}]
}
var cfgC = {
__isStock: false,
title: {
text: 'pie chart'
},
series: [{
type: 'pie',
name: 'one',
data: [
["A", 25],
["B", 25],
["C", 25],
["D", 25],
] // Instead of updating the initial data with the add function, the sequence can be updated by changing the chart configuration directly.
}]
};
var cfgD = {
extension: {
layout: 'single',
col: 8, // Specify the cell value for the width, the total value is 12
height: '300px',
},
title: {
text: 'handicap chart'
},
xAxis: {
type: 'datetime'
},
series: [{
name: 'buy one',
data: [],
}, {
name: 'sell one',
data: [],
}]
}
var cfgE = {
__isStock: false,
extension: {
layout: 'single',
col: 4,
height: '300px',
},
title: {
text: 'pie chart2'
},
series: [{
type: 'pie',
name: 'one',
data: [
["A", 25],
["B", 25],
["C", 25],
["D", 25],
]
}]
};
var chart = Chart([cfgA, cfgB, cfgC, cfgD, cfgE]);
chart.reset()
// Add a number of points to the pie chart, add can only update the data points added by add, built-in data points cannot be updated later.
chart.add(3, {
name: "ZZ",
y: Math.random() * 100
});
while (true) {
Sleep(1000)
var ticker = exchange.GetTicker()
if (!ticker) {
continue;
}
var diff = ticker.Sell - ticker.Buy
cfgA.subtitle = {
text: 'buy one ' + ticker.Buy + ', sell one ' + ticker.Sell,
};
cfgB.subtitle = {
text: 'spread ' + diff,
};
chart.add([0, [new Date().getTime(), ticker.Buy]]);
chart.add([1, [new Date().getTime(), ticker.Sell]]);
// Equivalent to updating the first data series of the second chart
chart.add([2, [new Date().getTime(), diff]]);
chart.add(4, [new Date().getTime(), ticker.Buy]);
chart.add(5, [new Date().getTime(), ticker.Buy]);
cfgC.series[0].data[0][1] = Math.random() * 100;
cfgE.series[0].data[0][1] = Math.random() * 100;
// update is actually the same as resetting the chart's configuration
chart.update([cfgA, cfgB, cfgC, cfgD, cfgE]);
}
}
import random
import time
def main():
cfgA = {
"extension" : {
"layout" : "single",
"height" : 300,
"col" : 8
},
"title" : {
"text" : "handicap chart"
},
"xAxis" : {
"type" : "datetime"
},
"series" : [{
"name" : "buy one",
"data" : []
}, {
"name" : "sell one",
"data" : []
}]
}
cfgB = {
"title" : {
"text" : "spread chart"
},
"xAxis" : {
"type" : "datetime",
},
"series" : [{
"name" : "spread",
"type" : "column",
"data" : []
}]
}
cfgC = {
"__isStock" : False,
"title" : {
"text" : "pie chart"
},
"series" : [{
"type" : "pie",
"name" : "one",
"data" : [
["A", 25],
["B", 25],
["C", 25],
["D", 25],
]
}]
}
cfgD = {
"extension" : {
"layout" : "single",
"col" : 8,
"height" : "300px"
},
"title" : {
"text" : "handicap chart"
},
"series" : [{
"name" : "buy one",
"data" : []
}, {
"name" : "sell one",
"data" : []
}]
}
cfgE = {
"__isStock" : False,
"extension" : {
"layout" : "single",
"col" : 4,
"height" : "300px"
},
"title" : {
"text" : "pie chart2"
},
"series" : [{
"type" : "pie",
"name" : "one",
"data" : [
["A", 25],
["B", 25],
["C", 25],
["D", 25]
]
}]
}
chart = Chart([cfgA, cfgB, cfgC, cfgD, cfgE])
chart.reset()
chart.add(3, {
"name" : "ZZ",
"y" : random.random() * 100
})
while True:
Sleep(1000)
ticker = exchange.GetTicker()
if not ticker :
continue
diff = ticker["Sell"] - ticker["Buy"]
cfgA["subtitle"] = {
"text" : "buy one" + str(ticker["Buy"]) + "sell one" + str(ticker["Sell"])
}
cfgB["subtitle"] = {
"text" : "spread " + str(diff)
}
chart.add(0, [time.time() * 1000, ticker["Buy"]])
chart.add(1, [time.time() * 1000, ticker["Sell"]])
chart.add(2, [time.time() * 1000, diff])
chart.add(4, [time.time() * 1000, ticker["Buy"]])
chart.add(5, [time.time() * 1000, ticker["Buy"]])
cfgC["series"][0]["data"][0][1] = random.random() * 100
cfgE["series"][0]["data"][0][1] = random.random() * 100
void main() {
json cfgA = R"({
"extension" : {
"layout" : "single",
"height" : 300,
"col" : 8
},
"title" : {
"text" : "handicap chart"
},
"xAxis" : {
"type" : "datetime"
},
"series" : [{
"name" : "buy one",
"data" : []
}, {
"name" : "sell one",
"data" : []
}]
})"_json;
json cfgB = R"({
"title" : {
"text" : "spread chart"
},
"xAxis" : {
"type" : "datetime"
},
"series" : [{
"name" : "spread",
"type" : "column",
"data" : []
}]
})"_json;
json cfgC = R"({
"__isStock" : false,
"title" : {
"text" : "pie chart"
},
"series" : [{
"type" : "pie",
"name" : "one",
"data" : [
["A", 25],
["B", 25],
["C", 25],
["D", 25]
]
}]
})"_json;
json cfgD = R"({
"extension" : {
"layout" : "single",
"col" : 8,
"height" : "300px"
},
"title" : {
"text" : "handicap chart"
},
"series" : [{
"name" : "buy one",
"data" : []
}, {
"name" : "sell one",
"data" : []
}]
})"_json;
json cfgE = R"({
"__isStock" : false,
"extension" : {
"layout" : "single",
"col" : 4,
"height" : "300px"
},
"title" : {
"text" : "pie chart2"
},
"series" : [{
"type" : "pie",
"name" : "one",
"data" : [
["A", 25],
["B", 25],
["C", 25],
["D", 25]
]
}]
})"_json;
auto chart = Chart({cfgA, cfgB, cfgC, cfgD, cfgE});
chart.reset();
json zz = R"({
"name" : "ZZ",
"y" : 0
})"_json;
zz["y"] = rand() % 100;
chart.add(3, zz);
while(true) {
Sleep(1000);
auto ticker = exchange.GetTicker();
if(!ticker.Valid) {
continue;
}
auto diff = ticker.Sell - ticker.Buy;
json cfgASubTitle = R"({"text" : ""})"_json;
cfgASubTitle["text"] = format("buy one %f , sell one %f", ticker.Buy, ticker.Sell);
cfgA["subtitle"] = cfgASubTitle;
json cfgBSubTitle = R"({"text" : ""})"_json;
cfgBSubTitle["text"] = format("spread %f", diff);
cfgB["subtitle"] = cfgBSubTitle;
chart.add(0, {Unix() * 1000, ticker.Buy});
chart.add(1, {Unix() * 1000, ticker.Sell});
chart.add(2, {Unix() * 1000, diff});
chart.add(4, {Unix() * 1000, ticker.Buy});
chart.add(5, {Unix() * 1000, ticker.Buy});
cfgC["series"][0]["data"][0][1] = rand() % 100;
cfgE["series"][0]["data"][0][1] = rand() % 100;
chart.update({cfgA, cfgB, cfgC, cfgD, cfgE});
}
}
Multi-chart drawing configuration:
extension.layout attribute
If the attribute is set with the value “single”, the charts will not be stacked (not displayed as tabs), but will be displayed separately (tiled).extension.height attribute
The attribute is used to set the height of the chart, either as a numeric value, or as “300px”.extension.col attribute
The attribute is used to set the width of the chart, the page width is divided into 12 cells, set 8 ,that is, the chart occupies 8 cells width.// This chart is an object in the JavaScript language, and before using the Chart function, we need to declare an object variable chart to configure the chart. var chart = {
// This field marks whether the chart is a general chart or not, if you are interested, you can change it to false and run it.
__isStock: true,
// Scaling tool
tooltip: {xDateFormat: '%Y-%m-%d %H:%M:%S, %A'},
// title
title : { text : 'spread analysis chart'},
// selection range
rangeSelector: {
buttons: [{type: 'hour',count: 1, text: '1h'}, {type: 'hour',count: 3, text: '3h'}, {type: 'hour', count: 8, text: '8h'}, {type: 'all',text: 'All'}],
selected: 0,
inputEnabled: false
},
// Coordinate axis horizontal axis that is: x-axis, the current setting type is: time
xAxis: { type: 'datetime'},
// Coordinate axis vertical axis that is: y-axis, default value adjusted with the size of the data
yAxis : {
// title
title: {text: 'spread'},
// Whether to enable the right vertical axis
opposite: false
},
// Data series, this sttribute holds the individual data series (lines, K-charts, labels, etc...)
series : [
// The index is 0, and the data array holds the data of the index series
{name : "line1", id : "line1,buy1Price", data : []},
// Index is 1, set dashStyle:'shortdash' i.e.: set the dashed line
{name : "line2", id : "line2,lastPrice", dashStyle : 'shortdash', data : []}
]
} function main(){
// Call the Chart function to initialize the chart
var ObjChart = Chart(chart)
// Clear out
ObjChart.reset()
while(true){
// Gets the timestamp of this poll, i.e. a millisecond timestamp. It's used to determine the position of the X-axis written to the chart.
var nowTime = new Date().getTime()
// Get the ticker data
var ticker = _C(exchange.GetTicker)
// Get buy one price from the return value of the ticker data
var buy1Price = ticker.Buy
// To obtain the final transaction price, we add 1 in order not to overlap the 2 lines
var lastPrice = ticker.Last + 1
// Data sequence with timestamp as X-value and buy one price as Y-value passed into index 0
ObjChart.add(0, [nowTime, buy1Price])
// ditto
ObjChart.add(1, [nowTime, lastPrice])
Sleep(2000)
}
}```
```python
import time
chart = {
"__isStock" : True,
"tooltip" : {"xDateFormat" : "%Y-%m-%d %H:%M:%S, %A"},
"title" : {"text" : "spread analysis chart"},
"rangeSelector" : {
"buttons" : [{"type": "count", "count": 1, "text": "1h"}, {"type": "hour", "count": 3, "text": "3h"}, {"type": "hour", "count": 8, "text": "8h"}, {"type": "all", "text": "All"}],
"selected": 0,
"inputEnabled": False
},
"xAxis": {"type": "datetime"},
"yAxis": {
"title": {"text": "spread"},
"opposite": False
},
"series": [{
"name": "line1", "id": "line1,buy1Price", "data": []
}, {
"name": "line2", "id": "line2,lastPrice", "dashStyle": "shortdash", "data": []
}]
}
def main():
ObjChart = Chart(chart)
ObjChart.reset()
while True:
nowTime = time.time() * 1000
ticker = exchange.GetTicker()
buy1Price = ticker["Buy"]
lastPrice = ticker["Last"] + 1
ObjChart.add(0, [nowTime, buy1Price])
ObjChart.add(1, [nowTime, lastPrice])
Sleep(2000)
void main() {
// When writing strategies in C++, try not to declare global variables that are not of the base type, so the chart configuration object is declared inside the main function.
json chart = R"({
"__isStock" : true,
"tooltip" : {"xDateFormat" : "%Y-%m-%d %H:%M:%S, %A"},
"title" : {"text" : "spread analysis chart"},
"rangeSelector" : {
"buttons" : [{"type": "count", "count": 1, "text": "1h"}, {"type": "hour", "count": 3, "text": "3h"}, {"type": "hour", "count": 8, "text": "8h"}, {"type": "all", "text": "All"}],
"selected": 0,
"inputEnabled": false
},
"xAxis": {"type": "datetime"},
"yAxis": {
"title": {"text": "spread"},
"opposite": false
},
"series": [{
"name": "line1", "id": "line1,buy1Price", "data": []
}, {
"name": "line2", "id": "line2,lastPrice", "dashStyle": "shortdash", "data": []
}]
})"_json;
auto ObjChart = Chart(chart);
ObjChart.reset();
while(true) {
auto nowTime = Unix() * 1000;
auto ticker = exchange.GetTicker();
auto buy1Price = ticker.Buy;
auto lastPrice = ticker.Last + 1.0;
ObjChart.add(0, {nowTime, buy1Price});
ObjChart.add(1, {nowTime, lastPrice});
Sleep(2000);
}
}
Example of a simple drawing:
// Objects used to initialize the chart
var chart = {
// Chart title
title: {text: "line value triggers the plotLines value"},
// Y-axis related settings
yAxis: {
// A horizontal line perpendicular to the Y-axis, used as a trigger line, is a structural array that can set multiple trigger lines
plotLines: [{
// The value of the trigger line, how much it set, this line will be displayed in the corresponding value position
value: 0,
// Set the color of the trigger line
color: 'red',
// Width
width: 2,
// Displaying labels
label: {
// Label text
text: 'Trigger value',
// Centered label position
align: 'center'
}
}]
},
// X-axis related settings, here the setting type is time axis
xAxis: {type: "datetime"},
series: [
{name: "sin", type: "spline", data: []},
// This is an important data series, you can set multiple data series, according to the array index control
{name: "cos", type: "spline", data: []}
]
}
function main(){
// Circumference
var pi = 3.1415926535897
// Variables for recording timestamps
var time = 0
// Angle
var angle = 0
// Coordinate y values for receiving sine and cosine values
var y = 0
// Call the API interface to initialize the chart with the chart object
var objChart = Chart(chart)
// Initially, clear the chart
objChart.reset()
// Set the value of the trigger line to 1
chart.yAxis.plotLines[0].value = 1
// Loop
while(true){
// Get the timestamp of the current moment
time = new Date().getTime()
// Angle increases by 5 degrees every 500ms and calculates the sine value
y = Math.sin(angle * 2 * pi / 360)
// Write the calculated y value to the data series of the corresponding index of the chart, the first parameter of the add function is the specified data series index
objChart.add(0, [time, y])
// Calculate the cosine value
y = Math.cos(angle * 2 * pi / 360)
objChart.add(1, [time, y])
// Increase by 5 degrees
angle += 5
// Pause for 5 seconds to avoid drawing too often and growing data too fast
Sleep(5000)
}
}
import math
import time
chart = {
"title": {"text": "line value triggers the plotLines value"},
"yAxis": {
"plotLines": [{
"value": 0,
"color": "red",
"width": 2,
"label": {
"text": "trigger value",
"align": "center"
}
}]
},
"xAxis": {"type": "datetime"},
"series": [{"name": "sin", "type": "spline", "data": []},
{"name": "cos", "type": "spline", "data": []}]
}
def main():
pi = 3.1415926535897
ts = 0
angle = 0
y = 0
objChart = Chart(chart)
objChart.reset()
chart["yAxis"]["plotLines"][0]["value"] = 1
while True:
ts = time.time() * 1000
y = math.sin(angle * 2 * pi / 360)
objChart.add(0, [ts, y])
y = math.cos(angle * 2 * pi / 360)
objChart.add(1, [ts, y])
angle += 5
Sleep(5000)
void main() {
json chart = R"({
"title": {"text": "line value triggers the plotLines value"},
"yAxis": {
"plotLines": [{
"value": 0,
"color": "red",
"width": 2,
"label": {
"text": "trigger value",
"align": "center"
}
}]
},
"xAxis": {"type": "datetime"},
"series": [{"name": "sin", "type": "spline", "data": []},
{"name": "cos", "type": "spline", "data": []}]
})"_json;
auto pi = 3.1415926535897;
auto ts = 0;
auto angle = 0.0;
auto y = 0.0;
auto objChart = Chart(chart);
objChart.reset();
chart["yAxis"]["plotLines"][0]["value"] = 1;
while(true) {
ts = Unix() * 1000;
y = sin(angle * 2 * pi / 360);
objChart.add(0, {ts, y});
y = cos(angle * 2 * pi / 360);
objChart.add(1, {ts, y});
angle += 5;
Sleep(5000);
}
}
Example of trigonometric curve drawing:
/*backtest
start: 2020-03-11 00:00:00
end: 2020-04-09 23:59:00
period: 1d
exchanges: [{"eid":"Bitfinex","currency":"BTC_USD"}]
*/
var chartCfg = {
subtitle: {
text: "subtitle",
},
yAxis: [{
height: "40%",
lineWidth: 2,
title: {
text: 'PnL',
},
tickPixelInterval: 20,
minorGridLineWidth: 1,
minorTickWidth: 0,
opposite: true,
labels: {
align: "right",
x: -3,
}
}, {
title: {
text: 'Profit',
},
top: "42%",
height: "18%",
offset: 0,
lineWidth: 2
}, {
title: {
text: 'Vol',
},
top: '62%',
height: '18%',
offset: 0,
lineWidth: 2
}, {
title: {
text: 'Asset',
},
top: '82%',
height: '18%',
offset: 0,
lineWidth: 2
}],
series: [{
name: 'PnL',
data: [],
id: 'primary',
tooltip: {
xDateFormat: '%Y-%m-%d %H:%M:%S'
},
yAxis: 0
}, {
type: 'column',
lineWidth: 2,
name: 'Profit',
data: [],
yAxis: 1,
}, {
type: 'column',
name: 'Trade',
data: [],
yAxis: 2
}, {
type: 'area',
step: true,
lineWidth: 0,
name: 'Long',
data: [],
yAxis: 2
}, {
type: 'area',
step: true,
lineWidth: 0,
name: 'Short',
data: [],
yAxis: 2
}, {
type: 'line',
step: true,
color: '#5b4b00',
name: 'Asset',
data: [],
yAxis: 3
}, {
type: 'pie',
innerSize: '70%',
name: 'Random',
data: [],
center: ['3%', '6%'],
size: '15%',
dataLabels: {
enabled: false
},
startAngle: -90,
endAngle: 90,
}],
};
function main() {
let c = Chart(chartCfg);
let preTicker = null;
while (true) {
let t = exchange.GetTicker();
c.add(0, [t.Time, t.Last]); // PnL
c.add(1, [t.Time, preTicker ? t.Last - preTicker.Last : 0]); // profit
let r = Math.random();
var pos = parseInt(t.Time/86400);
c.add(2, [t.Time, pos/2]); // Vol
c.add(3, [t.Time, r > 0.8 ? pos : null]); // Long
c.add(4, [t.Time, r < 0.8 ? -pos : null]); // Short
c.add(5, [t.Time, Math.random() * 100]); // Asset
// update pie
chartCfg.series[chartCfg.series.length-1].data = [
["A", Math.random()*100],
["B", Math.random()*100],
];
c.update(chartCfg)
preTicker = t;
}
}
'''backtest
start: 2020-03-11 00:00:00
end: 2020-04-09 23:59:00
period: 1d
exchanges: [{"eid":"Bitfinex","currency":"BTC_USD"}]
'''
import random
chartCfg = {
"subtitle": {
"text": "subtitle"
},
"yAxis": [{
"height": "40%",
"lineWidth": 2,
"title": {
"text": 'PnL'
},
"tickPixelInterval": 20,
"minorGridLineWidth": 1,
"minorTickWidth": 0,
"opposite": True,
"labels": {
"align": "right",
"x": -3
}
}, {
"title": {
"text": 'Profit'
},
"top": "42%",
"height": "18%",
"offset": 0,
"lineWidth": 2
}, {
"title": {
"text": 'Vol'
},
"top": '62%',
"height": '18%',
"offset": 0,
"lineWidth": 2
}, {
"title": {
"text": 'Asset'
},
"top": '82%',
"height": '18%',
"offset": 0,
"lineWidth": 2
}],
"series": [{
"name": 'PnL',
"data": [],
"id": 'primary',
"tooltip": {
"xDateFormat": '%Y-%m-%d %H:%M:%S'
},
"yAxis": 0
}, {
"type": 'column',
"lineWidth": 2,
"name": 'Profit',
"data": [],
"yAxis": 1
}, {
"type": 'column',
"name": 'Trade',
"data": [],
"yAxis": 2
}, {
"type": 'area',
"step": True,
"lineWidth": 0,
"name": 'Long',
"data": [],
"yAxis": 2
}, {
"type": 'area',
"step": True,
"lineWidth": 0,
"name": 'Short',
"data": [],
"yAxis": 2
}, {
"type": 'line',
"step": True,
"color": '#5b4b00',
"name": 'Asset',
"data": [],
"yAxis": 3
}, {
"type": 'pie',
"innerSize": '70%',
"name": 'Random',
"data": [],
"center": ['3%', '6%'],
"size": '15%',
"dataLabels": {
"enabled": False
},
"startAngle": -90,
"endAngle": 90
}]
}
def main():
c = Chart(chartCfg)
preTicker = None
while True:
t = exchange.GetTicker()
c.add(0, [t["Time"], t["Last"]])
profit = t["Last"] - preTicker["Last"] if preTicker else 0
c.add(1, [t["Time"], profit])
r = random.random()
pos = t["Time"] / 86400
c.add(2, [t["Time"], pos / 2])
long = pos if r > 0.8 else None
c.add(3, [t["Time"], long])
short = -pos if r < 0.8 else None
c.add(4, [t["Time"], short])
c.add(5, [t["Time"], random.random() * 100])
# update pie
chartCfg["series"][len(chartCfg["series"]) - 1]["data"] = [
["A", random.random() * 100],
["B", random.random() * 100]
]
c.update(chartCfg)
preTicker = t
/*backtest
start: 2020-03-11 00:00:00
end: 2020-04-09 23:59:00
period: 1d
exchanges: [{"eid":"Bitfinex","currency":"BTC_USD"}]
*/
void main() {
json chartCfg = R"({
"subtitle": {
"text": "subtitle"
},
"yAxis": [{
"height": "40%",
"lineWidth": 2,
"title": {
"text": "PnL"
},
"tickPixelInterval": 20,
"minorGridLineWidth": 1,
"minorTickWidth": 0,
"opposite": true,
"labels": {
"align": "right",
"x": -3
}
}, {
"title": {
"text": "Profit"
},
"top": "42%",
"height": "18%",
"offset": 0,
"lineWidth": 2
}, {
"title": {
"text": "Vol"
},
"top": "62%",
"height": "18%",
"offset": 0,
"lineWidth": 2
}, {
"title": {
"text": "Asset"
},
"top": "82%",
"height": "18%",
"offset": 0,
"lineWidth": 2
}],
"series": [{
"name": "PnL",
"data": [],
"id": "primary",
"tooltip": {
"xDateFormat": "%Y-%m-%d %H:%M:%S"
},
"yAxis": 0
}, {
"type": "column",
"lineWidth": 2,
"name": "Profit",
"data": [],
"yAxis": 1
}, {
"type": "column",
"name": "Trade",
"data": [],
"yAxis": 2
}, {
"type": "area",
"step": true,
"lineWidth": 0,
"name": "Long",
"data": [],
"yAxis": 2
}, {
"type": "area",
"step": true,
"lineWidth": 0,
"name": "Short",
"data": [],
"yAxis": 2
}, {
"type": "line",
"step": true,
"color": "#5b4b00",
"name": "Asset",
"data": [],
"yAxis": 3
}, {
"type": "pie",
"innerSize": "70%",
"name": "Random",
"data": [],
"center": ["3%", "6%"],
"size": "15%",
"dataLabels": {
"enabled": false
},
"startAngle": -90,
"endAngle": 90
}]
})"_json;
Chart c = Chart(chartCfg);
Ticker preTicker;
while(true) {
auto t = exchange.GetTicker();
c.add(0, {t.Time, t.Last});
auto profit = preTicker.Valid ? t.Last - preTicker.Last : 0;
c.add(1, {t.Time, profit});
auto r = rand() % 100;
auto pos = t.Time / 86400.0;
c.add(2, {t.Time, pos / 2.0});
auto longPos = r > 0.8 ? pos : NULL;
c.add(3, {t.Time, longPos});
auto shortPos = r < 0.8 ? -pos : NULL;
c.add(4, {t.Time, shortPos});
c.add(5, {t.Time, rand() % 100});
// update pie
json pie = R"([["A", 0], ["B", 0]])"_json;
pie[0][1] = rand() % 100;
pie[1][1] = rand() % 100;
chartCfg["series"][chartCfg["series"].size() - 1]["data"] = pie;
c.update(chartCfg);
preTicker = t;
}
}
Complex examples of using hybrid charts:
// update pie
chartCfg.series[chartCfg.series.length-1].data = [
["A", Math.random()*100],
["B", Math.random()*100],
];
c.update(chartCfg)
# update pie
chartCfg["series"][len(chartCfg["series"]) - 1]["data"] = [
["A", random.random() * 100],
["B", random.random() * 100]
]
c.update(chartCfg)
// update pie
json pie = R"([["A", 0], ["B", 0]])"_json;
pie[0][1] = rand() % 100;
pie[1][1] = rand() % 100;
chartCfg["series"][chartCfg["series"].size() - 1]["data"] = pie;
c.update(chartCfg);
Charts of type pie are charts without a timeline, and you need to update the chart configuration directly when updating the data. For example, the code in the above example updates the chart using c.update(chartCfg) after updating the data, as follows:
The Chart() function returns a chart object that has 4 methods: add(), reset(), update(), del().
update() method:
The update() method can update the chart configuration information. The parameter of this method is the Chart configuration object (JSON).del() method:
The del() method can delete the data series of the specified index based on the passed series parameter.add() method:
The add() method can write data to the chart, with the following parameters in order:series: used to set the data series index, which is an integer.data: used to set the specific data to be written, it is an array.index (optional): used to set the data index, it’s an integer. Specify the specific index position of the modified data, and it supports negative numbers, the setting is -1 refers to the last data in the data set.
For example, when drawing a line, modify the data on the last point of the line: chart.add(0, [1574993606000, 13.5], -1), that is, change the data on the penultimate first point of the chart series[0].data.
The index parameter is not set, which means that the data is added to the last point of the current data series.reset() method:
The reset() method is used to empty the chart data. The reset() method can take a parameter remain to specify the number of entries to keep. No parameter remain is passed to clear all data.{@fun/Log/KLineChart KLineChart}
EnableLog KLineChart