// Downloaded From https://www.WiseStockTrader.com
HalfLife	= Param("channel halflife", 4.5, 0, 10, 0.1, 0);
ChanLen	= Param("channel length", 1, 1, 100, 1, 0);

shrink		= 2^(-HalfLife);
shrink2	= 1 - shrink;

topChan[0]	= High[0];
botChan[0]	= Low[0];

HH	= HHV(High, ChanLen);
LL	= LLV(Low, Chanlen); 

for( i = 1; i < BarCount; i++ ) {
	topChan[i] = shrink * H[i] + shrink2 * topChan[i-1] ;
	botChan[i] = shrink * L[i] + shrink2 * botChan[i-1] ;
	if (HH[i] >= topChan[i])	topChan[i] = HH[i];
	if (LL[i] <= botChan[i])	botChan[i] = LL[i];
	}

Plot(topChan,"spandex", colorRed, styleThick);
Plot(botChan,"", colorRed, styleThick);

//for( i = 1; i < BarCount; i++ ) { 
//	if (HH[i] >= topChan[i-1])			topChan[i] = HH[i];
//	else							    	topChan[i] = shrink * HH[i] + shrink2 * topChan[i-1] ;
//	if (LL[i] <= botChan[i-1])			botChan[i] = LL[i];
//	else							    	botChan[i] = shrink * LL[i] + shrink2 * botChan[i-1] ;
//	}