JavaScript StockChart with Price & Volume

window.onload = function () {
  var dataPoints1 = [], dataPoints2 = [], dataPoints3 = [];
  var stockChart = new CanvasJS.StockChart("chartContainer",{
    theme: "light2",
    exportEnabled: true,
    title:{
      text:"Bitcoin Price & Volume"
    },
    charts: [{
      toolTip: {
        shared: true
      },
      axisX: {
        lineThickness: 5,
        tickLength: 0,
        labelFormatter: function(e) {
          return "";
        }
      },
      axisY: {
        prefix: "$"
      },
      legend: {
        verticalAlign: "top"
      },
      data: [{
        showInLegend: true,
        name: "Stock Price (in USD)",
        yValueFormatString: "$#,###.##",
        type: "candlestick",
        dataPoints : dataPoints1
      }]
    },{
      height: 100,
      toolTip: {
        shared: true
      },
      axisY: {
        prefix: "$",
        labelFormatter: addSymbols
      },
      legend: {
        verticalAlign: "top"
      },
      data: [{
        showInLegend: true,
        name: "Volume (BTC/USD)",
        yValueFormatString: "$#,###.##",
        dataPoints : dataPoints2
      }]
    }],
    navigator: {
      data: [{
        dataPoints: dataPoints3
      }],
      slider: {
        minimum: new Date(2018, 06, 01),
        maximum: new Date(2018, 08, 01)
      }
    }
  });
  $.getJSON("https://canvasjs.com/data/docs/btcusd2018.json", function(data) {
    for(var i = 0; i < data.length; i++){
      dataPoints1.push({x: new Date(data[i].date), y: [Number(data[i].open), Number(data[i].high), Number(data[i].low), Number(data[i].close)]});;
      dataPoints2.push({x: new Date(data[i].date), y: Number(data[i].volume_usd)});
      dataPoints3.push({x: new Date(data[i].date), y: Number(data[i].close)});
    }
    stockChart.render();
  });
  function addSymbols(e){
    var suffixes = ["", "K", "M", "B"];
    var order = Math.max(Math.floor(Math.log(Math.abs(e.value)) / Math.log(1000)), 0);
    if(order > suffixes.length - 1)
      order = suffixes.length - 1;
    var suffix = suffixes[order];
    return CanvasJS.formatNumber(e.value / Math.pow(1000, order)) + suffix;
  }
}