Web 3.0 Explorable #1: Order Book
html`<div id="chartdiv"></div>`
am4core.ready(function() {
// Themes begin
// Themes end
// Create chart instance
var chart = am4core.create("chartdiv", am4charts.XYChart);
// Add data
chart.dataSource.url = "https://poloniex.com/public?command=returnOrderBook¤cyPair=BTC_ETH&depth=50";
chart.dataSource.reloadFrequency = 30000;
chart.dataSource.adapter.add("parsedData", function(data) {
// Function to process (sort and calculate cummulative volume)
function processData(list, type, desc) {
// Convert to data points
for(var i = 0; i < list.length; i++) {
list[i] = {
value: Number(list[i][0]),
volume: Number(list[i][1]),
}
}
// Sort list just in case
list.sort(function(a, b) {
if (a.value > b.value) {
return 1;
}
else if (a.value < b.value) {
return -1;
}
else {
return 0;
}
});
// Calculate cummulative volume
if (desc) {
for(var i = list.length - 1; i >= 0; i--) {
if (i < (list.length - 1)) {
list[i].totalvolume = list[i+1].totalvolume + list[i].volume;
}
else {
list[i].totalvolume = list[i].volume;
}
var dp = {};
dp["value"] = list[i].value;
dp[type + "volume"] = list[i].volume;
dp[type + "totalvolume"] = list[i].totalvolume;
res.unshift(dp);
}
}
else {
for(var i = 0; i < list.length; i++) {
if (i > 0) {
list[i].totalvolume = list[i-1].totalvolume + list[i].volume;
}
else {
list[i].totalvolume = list[i].volume;
}
var dp = {};
dp["value"] = list[i].value;
dp[type + "volume"] = list[i].volume;
dp[type + "totalvolume"] = list[i].totalvolume;
res.push(dp);
}
}
}
// Init
var res = [];
processData(data.bids, "bids", true);
processData(data.asks, "asks", false);
return res;
});
// Set up precision for numbers
chart.numberFormatter.numberFormat = "#,###.####";
// Create axes
var xAxis = chart.xAxes.push(new am4charts.CategoryAxis());
xAxis.dataFields.category = "value";
//xAxis.renderer.grid.template.location = 0;
xAxis.renderer.minGridDistance = 50;
xAxis.title.text = "Price (BTC/ETH)";
var yAxis = chart.yAxes.push(new am4charts.ValueAxis());
yAxis.title.text = "Volume";
// Create series
var series = chart.series.push(new am4charts.StepLineSeries());
series.dataFields.categoryX = "value";
series.dataFields.valueY = "bidstotalvolume";
series.strokeWidth = 2;
series.stroke = am4core.color("#0f0");
series.fill = series.stroke;
series.fillOpacity = 0.1;
series.tooltipText = "Ask: [bold]{categoryX}[/]\nTotal volume: [bold]{valueY}[/]\nVolume: [bold]{bidsvolume}[/]"
var series2 = chart.series.push(new am4charts.StepLineSeries());
series2.dataFields.categoryX = "value";
series2.dataFields.valueY = "askstotalvolume";
series2.strokeWidth = 2;
series2.stroke = am4core.color("#f00");
series2.fill = series2.stroke;
series2.fillOpacity = 0.1;
series2.tooltipText = "Ask: [bold]{categoryX}[/]\nTotal volume: [bold]{valueY}[/]\nVolume: [bold]{asksvolume}[/]"
var series3 = chart.series.push(new am4charts.ColumnSeries());
series3.dataFields.categoryX = "value";
series3.dataFields.valueY = "bidsvolume";
series3.strokeWidth = 0;
series3.fill = am4core.color("#000");
series3.fillOpacity = 0.2;
var series4 = chart.series.push(new am4charts.ColumnSeries());
series4.dataFields.categoryX = "value";
series4.dataFields.valueY = "asksvolume";
series4.strokeWidth = 0;
series4.fill = am4core.color("#000");
series4.fillOpacity = 0.2;
// Add cursor
chart.cursor = new am4charts.XYCursor();
}); // end am4core.ready()
html`<style> #chartdiv { width: 100%; height: 500px; } </style>`
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