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BollingerBands

interface cAlgo.API.Indicators

DesktopCLICloud

Bollinger Bands are used to confirm signals. The bands indicate overbought and oversold levels relative to a moving average.

Definition

public interface BollingerBands

Namespace: cAlgo.API.Indicators · Group: Indicators · Implements: StandardIndicator

Remarks

Bollinger bands widen in volatile market periods, and contract during less volatile periods. Tightening of the bands is often used a signal that there will shortly be a sharp increase in market volatility.

Examples

Example 1

var bollingerBands = Indicators.BollingerBands(Bars.ClosePrices, 20, 2, MovingAverageType.Simple);
Print("Top: {0}, Main: {1}, Bottom: {2}", bollingerBands.Top.LastValue, bollingerBands.Main.LastValue, bollingerBands.Bottom.LastValue);

bollingerBands = api.Indicators.BollingerBands(api.Bars.ClosePrices, 20, 2, MovingAverageType.Simple)
api.Print(f"Top: {bollingerBands.Top.LastValue}, Main: {bollingerBands.Main.LastValue}, Bottom: {bollingerBands.Bottom.LastValue}")

Example 2

using cAlgo.API;
using cAlgo.API.Indicators;

namespace cAlgo.Robots
{
    // This sample cBot shows how to use the Bollinger Bands indicator
    public partial class BollingerBandsSample : Robot
    {
        private double _volumeInUnits;

        private BollingerBands _bollingerBands;

        public Position[] BotPositions
        {
            get
            {
                return Positions.FindAll(Label);
            }
        }

        protected override void OnStart()
        {
            _volumeInUnits = Symbol.QuantityToVolumeInUnits(VolumeInLots);

            _bollingerBands = Indicators.BollingerBands(Source, 14, 2, MovingAverageType.Exponential);
        }

        protected override void OnBar()
        {
            if (Bars.LowPrices.Last(1) <= _bollingerBands.Bottom.Last(1) && Bars.LowPrices.Last(2) > _bollingerBands.Bottom.Last(2))
            {
                ClosePositions(TradeType.Sell);

                ExecuteMarketOrder(TradeType.Buy, SymbolName, _volumeInUnits, Label);
            }
            else if (Bars.HighPrices.Last(1) >= _bollingerBands.Top.Last(1) && Bars.HighPrices.Last(2) < _bollingerBands.Top.Last(2))
            {
                ClosePositions(TradeType.Buy);

                ExecuteMarketOrder(TradeType.Sell, SymbolName, _volumeInUnits, Label);
            }
        }

        private void ClosePositions(TradeType tradeType)
        {
            foreach (var position in BotPositions)
            {
                if (position.TradeType != tradeType) continue;

                ClosePosition(position);
            }
        }
    }
}

import clr

clr.AddReference("cAlgo.API")

# Import cAlgo API types
from cAlgo.API import *

# Import trading wrapper functions
from robot_wrapper import *

class BollingerBandsSample():
    def on_start(self):
        self.volumeInUnits = api.Symbol.QuantityToVolumeInUnits(api.VolumeInLots)
        self.bollingerBands = api.Indicators.BollingerBands(api.Source, 14, 2, MovingAverageType.Exponential)

    def on_bar_closed(self):
        if api.Bars.LowPrices.Last(0) <= self.bollingerBands.Bottom.Last(0) and api.Bars.LowPrices.Last(1) > self.bollingerBands.Bottom.Last(1):
            self.close_positions(TradeType.Sell)
            api.ExecuteMarketOrder(TradeType.Buy, api.SymbolName, self.volumeInUnits, api.Label)
        elif api.Bars.HighPrices.Last(0) >= self.bollingerBands.Top.Last(0) and api.Bars.HighPrices.Last(1) < self.bollingerBands.Top.Last(1):
            self.close_positions(TradeType.Buy)
            api.ExecuteMarketOrder(TradeType.Sell, api.SymbolName, self.volumeInUnits, api.Label)

    def get_bot_positions(self):
        return api.Positions.FindAll(api.Label)

    def close_positions(self, tradeType):
        for position in self.get_bot_positions():
            if position.TradeType != tradeType:
                continue
            api.ClosePosition(position)

{
  "AccessRights": "None",
  "TimeZone": "UTC",
  "Parameters": [
    {
      "Name": "VolumeInLots",
      "DisplayName": "Volume (Lots)",
      "Type": "Double",
      "DefaultValue": 0.01
    },
    {
      "Name": "Label",
      "Type": "String",
      "DefaultValue": "Sample"
    },
    {
      "Name": "Source",
      "Type": "DataSeries"
    }
  ]
}

Properties

Name Description
BottomDesktopCLICloudIndicatorDataSeries Lower Bollinger Band.
MainDesktopCLICloudIndicatorDataSeries Moving Average (Middle Bollinger Band).
TopDesktopCLICloudIndicatorDataSeries Upper Bollinger Band.

Inherited members

From StandardIndicator: AddToChart, Symbol, TimeFrame, Bars