2001 Oct: Trend Detection Index

[eSignal]

File Name: TrendDetectionIndex.efs

Description:
Trend Detection Index

Formula Parameters:
Length: 20
Thickness: 2
Line Color: Green
Display Cursor Labels: True


Notes:
The related article is copyrighted material. If you are not
a subscriber of Stocks & Commodities, please visit www.traders.com.


Download File:
TrendDetectionIndex.efs



EFS Code:

/*********************************
Provided By:  
    eSignal (Copyright c eSignal), a division of Interactive Data 
    Corporation. 2008. 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:        
    Trend Detection Index 

Version:            1.0  01/12/2009

Formula Parameters:                     Default:
    Length                              20
    Thickness                           2
    Line Color                          Green
    Display Cursor Labels               True

Notes: 
    The related article is copyrighted material. If you are not
    a subscriber of Stocks & Commodities, please visit [url]www.traders.com.[/url]

**********************************/

var fpArray = new Array();
var bInit = false;

function preMain() {
    setPriceStudy(false);
    setShowCursorLabel(false);
    setShowTitleParameters( false );
    setStudyTitle("Trend Detection Index");
    setCursorLabelName("Position", 0);
    setDefaultBarFgColor(Color.green, 0);
    setPlotType(PLOTTYPE_LINE, 0); 
    setDefaultBarThickness(2, 0);
    setStudyMax(1.1);
    setStudyMin(-1.1);
   
    askForInput();
    var x=0;
    fpArray[x] = new FunctionParameter("LineColor", FunctionParameter.COLOR);
    with(fpArray[x++]){
        setName("Line Color");
        setDefault(Color.green);
    }    

    fpArray[x] = new FunctionParameter("ViewValue", FunctionParameter.BOOLEAN);
    with(fpArray[x++]){
        setName("Display Cursor Labels");
        setDefault(false);
    }    
    
    fpArray[x] = new FunctionParameter("Length", FunctionParameter.NUMBER);
    with(fpArray[x++]){
        setLowerLimit(1);        
        setDefault(20);
    }

    fpArray[x] = new FunctionParameter("Thickness", FunctionParameter.NUMBER);
    with(fpArray[x++]){
        setName("Line Thickness");
        setLowerLimit(1);        
        setDefault(2);
    }
}

var xMom = null;
var xMomAbs = null;
var nMomSum_Prev = 0;
var nMomSum = 0;
var nMktPos_Prev = 0;
var nMktPos = 0;
var nTDL_Prev = 0;
var nTDL = 0;

function main(Length, Thickness, LineColor, ViewValue) {
var nLength2 =  2 * Length; 
var nMomSumAbs = 0;
var nMomAbsSum = 0;
var nMomAbsSum2 = 0;
var nState = getBarState();

    if ( bInit == false ) { 
        setDefaultBarFgColor(LineColor, 0);
        setDefaultBarThickness(Thickness, 0);
        setShowCursorLabel(ViewValue);        
        xMom = efsInternal("Calc_Mom", Length);
        xMomAbs = efsInternal("Calc_MomAbs", xMom);
        bInit = true; 
    } 

    if (getCurrentBarCount() < Length) return;

    if (nState == BARSTATE_NEWBAR) {
        nMomSum_Prev = nMomSum;
        nMktPos_Prev = nMktPos;
        nTDL_Prev = nTDL;
    }

    nMomSum = Summation1(Length); 
    nMomSumAbs = Math.abs(nMomSum); 
    nMomAbsSum = Summation2(Length); 
    nMomAbsSum2 = Summation2(nLength2); 

    nTDL = nMomSumAbs - (nMomAbsSum2 - nMomAbsSum); 

    if (nTDL_Prev > 0 ) {
        if( nMomSum_Prev > 0) nMktPos =  1; else nMktPos =  (-1);
    } else {
        nMktPos =  nMktPos_Prev;
    }

    return nMktPos;
}

function Calc_MomAbs(xMom){
var nRes = 0;
    nRes = Math.abs( xMom.getValue(0)); 
    if (nRes == null) nRes = 1;
    return nRes;
}

function Calc_Mom(nLength){
var nRes = 0;
    nRes = close(0) - close(-nLength);     
    if (nRes == null) nRes = 1;     
    return nRes;
}

function Summation1(nLength){
var nRes = 0;
    if (xMom.getValue(-nLength) == null) return 1;
    for (var i = nLength - 1; i >= 0; i--) {
        nRes += xMom.getValue(-i);
    }
    return nRes;
}

function Summation2(nLength){
var nRes = 0;
    if (xMomAbs.getValue(-nLength) == null) return 1;
    for (var i = nLength - 1; i >= 0; i--) {
        nRes += xMomAbs.getValue(-i);
    }
    return nRes;
}