Syntax

Public function BollingerBands(ByRef Data As Database, ByRef Source As Field, ByVal Periods As Integer, ByVal StandardDeviations As Long, ByVal MAType As Integer) As RecordSet

Overview

Bollinger Bands are similar in comparison to moving average envelopes. Bollinger Bands are calculated using standard deviations instead of shifting bands by a fixed percentage.

Interpretation

Bollinger Bands (as with most bands) can be imposed over an actual price or another indicator.
When prices rise above the upper band or fall below the lower band, a change in direction may occur when the price penetrates the band after a small reversal from the opposite direction.

Note

StandardDeviations is an integer specifying the value to use in the standard deviations calculation.
MAType is an integer specifying the moving average type to be used (Simple = 1, Exponential = 2, TimeSeries = 3, Variable = 4, Triangular = 5, Weighted = 6, VIDYA = 7).

Class: Bands

Parameters

Sample

Public Sub main()

        'Variables

        Dim _symbolInfo As VTLGeneral.CSymbol=ClientCode.GetSymbolByName("GOLD")

        Dim DB As New VTLGeneral.Database()

        Dim rsOHLCV As New VTLGeneral.RecordSet()

        Dim RecordCount As Integer

        Dim m_Recordset As VTLGeneral.RecordSet

        Dim _historyData As object()

        Dim output As String

        Dim Record As Integer

        Dim m_Date As VTLGeneral.Field

        Dim m_Open As VTLGeneral.Field

        Dim m_High As VTLGeneral.Field

        Dim m_Low As VTLGeneral.Field

        Dim m_Close As VTLGeneral.Field

        Dim j As Integer = 0

        Dim i As Integer = 0

        Dim _recordCount As Integer =100
        

        m_Recordset = DB.CreateRecord

        m_Open = New VTLGeneral.Field

        m_High = New VTLGeneral.Field

        m_Low = New VTLGeneral.Field

        m_Close = New VTLGeneral.Field
 

        DB.RecordCount = _recordCount

        RecordCount = _recordCount
 

        'Initialize Recordsets

        m_Open.initialize(_recordCount-1, "Open")

        m_High.initialize(_recordCount-1, "High")

        m_Low.initialize(_recordCount-1, "Low")

        m_Close.initialize(_recordCount-1, "Close")


        'load high, low ,open and data

         _historyData = ClientCode.GetChartHistory(_symbolInfo.ID, VTLGeneral.ENUM_PERIOD.Day,VTLGeneral.ENUM_HISTORY_TYPE.HIS_HIGH, _recordCount)
 

         For i  = 0 To _recordCount-1

                m_High.setValue(i,_historyData(i))

         Next
 

        _historyData = ClientCode.GetChartHistory(_symbolInfo.ID, VTLGeneral.ENUM_PERIOD.Day,VTLGeneral.ENUM_HISTORY_TYPE.HIS_LOW, _recordCount)
 

        For i  = 0 To _recordCount-1

                m_Low.setValue(i,_historyData(i))

        Next 


        _historyData = ClientCode.GetChartHistory(_symbolInfo.ID, VTLGeneral.ENUM_PERIOD.Day,VTLGeneral.ENUM_HISTORY_TYPE.HIS_OPEN, _recordCount)
 

        For i  = 0 To _recordCount-1

                m_Open.setValue(i,_historyData(i))

        Next 


        _historyData = ClientCode.GetChartHistory(_symbolInfo.ID, VTLGeneral.ENUM_PERIOD.Day,VTLGeneral.ENUM_HISTORY_TYPE.HIS_CLOSE, _recordCount)
 

        For i  = 0 To _recordCount-1

                m_Close.setValue(i,_historyData(i))

        Next 
 

        m_Recordset.addField(m_Open)

        m_Recordset.addField(m_High)

        m_Recordset.addField(m_Low)

        m_Recordset.addField(m_Close)
 

        'BollingerBands indicator

        Dim _indRecord As New  VTLGeneral.RecordSet()

        Dim bnd As New VTLGeneral.Bands()

        _indRecord = bnd.BollingerBands(DB,m_Open,14,2,1)
 

        For i = 0 To DB.getRecordCount-1

                output = output  &  CSTR(_indRecord.getValue("BollingerBandsMedian", i) ) & vbcrlf

        Next
 

        GUI.MsgDialog(output)

 

End Sub

 
 

See Also

• High Low Bands
• Moving Average Envelope
• FractalChaosBands

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