Bill Williams Alligator Averages

[eSignal]

File Name: ABillW_Alligator.efs

Description:
Bill Williams Alligator Averages

Formula Parameters:
Length Slow 21
Length Medium 13
Length Fast 8
Offset Slow 8
Offset Medium 5
Offset Fast 3


Notes:
This indicator calculates 3 Moving Averages for 21, 13 and 8 days,
with displacement 8, 5 and 3 days: Median Price (High+Low/2).


Download File:
ABillW_Alligator.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:        
    Bill Williams Alligator Averages

Version:            1.0  09/24/2008

Notes:
    This indicator calculates 3 Moving Averages for 21, 13 and 8 days,
    with displacement 8, 5 and 3 days: Median Price (High+Low/2).

Formula Parameters:                     Default:
    Length Slow                             21
    Length Medium                           13
    Length Fast                             8
    Offset Slow                             8
    Offset Medium                           5
    Offset Fast                             3                                     
**********************************/



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


function preMain() {

    setPriceStudy(true);
    setStudyTitle("Alligator");

    setCursorLabelName("Plot1", 0);
    setCursorLabelName("Plot2", 1);
    setCursorLabelName("Plot3", 2);

    setDefaultBarFgColor(Color.blue, 0);
    setDefaultBarFgColor(Color.red, 1); 
    setDefaultBarFgColor(Color.green, 2);

    setDefaultBarFgColor(Color.black, 3); 

 

    var x=0;
    fpArray[x] = new FunctionParameter("LengthSlow", FunctionParameter.NUMBER);
    with(fpArray[x++]){
        setName("Length Slow"); 
        setLowerLimit(1);  
        setDefault(21);
    }



    fpArray[x] = new FunctionParameter("OffsetSlow", FunctionParameter.NUMBER);

    with(fpArray[x++]){
        setName("Offset Slow");
        setLowerLimit(1);  
        setDefault(8);
    }

    

    fpArray[x] = new FunctionParameter("LengthMedium", FunctionParameter.NUMBER);
    with(fpArray[x++]){
        setName("Length Medium"); 
        setLowerLimit(1);  
        setDefault(13);
    }



    fpArray[x] = new FunctionParameter("OffsetMedium", FunctionParameter.NUMBER);
    with(fpArray[x++]){
        setName("Offset Medium");
        setLowerLimit(1);  
        setDefault(5);
    }

    

    fpArray[x] = new FunctionParameter("LengthFast", FunctionParameter.NUMBER);
    with(fpArray[x++]){
        setName("Length Fast"); 
        setLowerLimit(1);  
        setDefault(8);
    }



    fpArray[x] = new FunctionParameter("OffsetFast", FunctionParameter.NUMBER);
    with(fpArray[x++]){
        setName("Offset Fast");
        setLowerLimit(1);  
        setDefault(3);
    }
}



var xhl2 = null;
var xEMA1 = null;
var xEMA2 = null;
var xEMA3 = null;


function main(LengthSlow, OffsetSlow, LengthMedium, OffsetMedium, LengthFast, OffsetFast) {
var nXA1 = 0;
var nXA2 = 0;
var nXA3 = 0;


    if (LengthSlow == null) LengthSlow = 21;
    if (OffsetSlow == null) OffsetSlow = 8;
    if (LengthMedium == null) LengthMedium = 13;
    if (OffsetMedium == null)  OffsetMedium = 5;
    if (LengthFast == null) LengthFast = 8;
    if (OffsetFast == null) OffsetFast = 3;



    if ( bInit == false ) {
        xhl2 = hl2();
        xEMA1 = offsetSeries(ema(LengthSlow, xhl2), OffsetSlow);
        xEMA2 = offsetSeries(ema(LengthMedium, xhl2), OffsetMedium);
        xEMA3 = offsetSeries(ema(LengthFast, xhl2), OffsetFast);
        bInit = true; 
    } 


    nXA1 = xEMA1.getValue(0);
    nXA2 = xEMA2.getValue(0);
    nXA3 = xEMA3.getValue(0);

    return new Array(nXA1, nXA2, nXA3);
}