Modified Donchian Channels

ModifiedDonchianChannels.efs  
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File Name: ModifiedDonchianChannels.efs

Description:
Modified Donchian Channels

Formula Parameters:

• Length : 24
• Extremes : 3
• Margins : 0

Notes:

Download File:
ModifiedDonchianChannels.efs


EFS Code:

/*********************************
Provided By:  
    eSignal (Copyright c eSignal), a division of Interactive Data 
    Corporation. 2009. All rights reserved. This sample eSignal 
    Formula Script (EFS) is for educational purposes only and may be 
    modified and saved under a new file name.  eSignal is not responsible
    for the functionality once modified.  eSignal reserves the right 
    to modify and overwrite this EFS file with each new release.

Description:        
    Modified Donchian Channels
    
Version:            1.0  10/29/2009
 
Formula Parameters:                     Default:
    Length                              24
    Extremes                            3
    Margins                             0
    
Notes:
    
**********************************/
var fpArray = new Array();
var bInit = false;

function preMain(){
    setPriceStudy(true);
    setShowCursorLabel(true);
    setShowTitleParameters(false);
    setStudyTitle("Modified Donchian Channels");
    setCursorLabelName("Up Band", 0);
    setPlotType(PLOTTYPE_LINE, 0);
    setDefaultBarFgColor(Color.red, 0);
    setCursorLabelName("Dn Band", 1);    
    setPlotType(PLOTTYPE_LINE, 1);
    setDefaultBarFgColor(Color.red, 1);
    var x = 0;
    fpArray[x] = new FunctionParameter("Length", FunctionParameter.NUMBER);
    with(fpArray[x++]) {
        setLowerLimit(1);
        setDefault(24);
    }    
    fpArray[x] = new FunctionParameter("Margins", FunctionParameter.NUMBER);
    with(fpArray[x++]) {
        setLowerLimit(0);
        setDefault(0);
    }        
    fpArray[x] = new FunctionParameter("Extremes", FunctionParameter.NUMBER);
	with(fpArray[x++]){
        addOption(1); 
        addOption(2);
        addOption(3);
        setDefault(3); 
    }    
}

var xDonchUp = null;
var xDonchDn = null;
var xDonchOpenUp = null;
var xDonchOpenDn = null;

function main(Length, Extremes, Margins) {
var nBarState = getBarState();
var nDonchUp = 0;
var nDonchDn = 0;
var nDonchOpenUp = 0;
var nDonchOpenDn = 0;
var nSsMax = 0;
var nSsMin = 0;
var nmin = 0;
var nmax = 0;
    if (nBarState == BARSTATE_ALLBARS) {
        if(Length == null) Length = 24;
        if(Extremes == null) Extremes = 3;
        if(Margins == null) Margins = 0;
	}
	if (bInit == false) {
        xDonchUp = upperDonchian(Length, high());
        xDonchDn = lowerDonchian(Length, low());
        xDonchOpenUp = upperDonchian(Length, open());
        xDonchOpenDn = lowerDonchian(Length, open());
        bInit = true;
	}
    nDonchUp = xDonchUp.getValue(0);
    nDonchDn = xDonchDn.getValue(0)
    nDonchOpenUp = xDonchOpenUp.getValue(0);
    nDonchOpenDn = xDonchOpenDn.getValue(0);
    if (nDonchUp == null) return;
    if (Extremes ==1) {
        nSsMax = nDonchUp;
        nSsMin = nDonchDn;
    } else {
        if (Extremes == 3) {
            nSsMax = (nDonchOpenUp + nDonchUp) / 2;
            nSsMin = (nDonchOpenDn + nDonchDn) / 2;
        } else {
            nSsMax = nDonchOpenUp;
            nSsMin = nDonchOpenDn;
        }
    }    
    nmin = nSsMin + (nSsMax - nSsMin) * Margins / 100;
    nmax = nSsMax - (nSsMax - nSsMin) * Margins / 100;
    return new Array(nmax, nmin);
}