KeltnerAtrEmaAdj.efs

ICE Data Services -

KeltnerAtrEmaAdj.efs  

File Name: KeltnerAtrEmaAdj.efs

Description:
Keltner study with a 20 period exponential moving average of the basis line and bands based on 2.5 * Average True Range.

Formula Parameters:

  • nInputLength: Default is 20 (number of periods for basis line)
  • nRangeFactor: Default is 2.5 (multiplier for the bands)

Notes:
NA

 

Download File:
KeltnerAtrEmaAdj.efs



EFS Code:

/*****************************************************************
Provided By : eSignal. (c) Copyright 2003
*****************************************************************/

function preMain() {
    setPriceStudy(true);
    
    setStudyTitle("Keltner (ATR Bands) ");

    setCursorLabelName("K-Upper", 0);
    setCursorLabelName("K-Basis", 1);
    setCursorLabelName("K-Lower", 2);

    setDefaultBarFgColor(Color.blue, 0); // upper
	setDefaultBarFgColor(Color.red, 1); // basis
	setDefaultBarFgColor(Color.blue, 2); // lower
}

function ATR(nInputLength) {
    var dSum = 0;
    var dH = high(0, -nInputLength);
    var dL = low(0, -nInputLength);
    var dC = close(-1, -nInputLength);
    if (dH == null || dL == null || dC == null) {
        return;
    }
    for (i = 0; i < nInputLength; ++i) {
        var vTrueHigh = Math.max(dH[i], dC[i]);
        var vTrueLow = Math.min(dL[i], dC[i]);
        var vTrueRange = (vTrueHigh - vTrueLow);
        dSum += vTrueRange;
    }
    dSum /= nInputLength;
    return dSum;
}

var BarCntr = 0;
function main(nInputLength, nRangeFactor) {
	if(nInputLength == null)
		nInputLength = 20;
	if(nInputLength <= 0)
		nInputLength = 20;

	if(nRangeFactor == null)
		nRangeFactor = 2.5;
	if(nRangeFactor <= 0)
		nRangeFactor = 2.5;

    if (getBarState() == BARSTATE_NEWBAR)
        BarCntr += 1;
    
    if (BarCntr < nInputLength) {
        return;
    } else {
        var dKeltnerBasis= call("/Library/KeltnerEMA.efs", nInputLength);
        var dATR = ATR(nInputLength);
        return new Array(dKeltnerBasis + (nRangeFactor * dATR), dKeltnerBasis, dKeltnerBasis - (nRangeFactor * dATR));
    }
}