def isupfractal;
def isdownfractal;

# Looking for high and low series of equalities
# checking for possible fractal formation

rec hicount = if (high == high[1], hicount[1] + 1, 0);
# if the last bar high is the same as this bar’s high, increment
# otherwise set false(0)

rec hivalid = if ((hicount[1] == 0 and hicount == 1 and high > high[2] and high > high[3]) or (hicount[1] and hicount and hivalid[1] ), 1, 0) ;
# set hivalid to true(1)
# if we are entering an equality series, check if the 2 bars preceding the first equal bar # are lower than the current bar
# or if the last bar was an equal bar and this bar is an equal bar and the current equal
# series is valid
# otherwise it is false

rec locount = if (low == low[1], locount[1] + 1, 0);
rec lovalid = if ((locount[1] == 0 and locount == 1 and low < low[2] and low high[1] and high > high[2])) and high > high[-1] and high > high[-2], high, 0);
# Ok this is complicated, basically its checking if there were a series of equal bars and
# if the two bars before the first equal bar were lower
# or if the last 2 bars were lower than the current bar
# and if the two following 2 bars are lower than the current bar

# Checking for a traditional or non-standard down fractal

isdownfractal = if(((locount and lovalid) or (low < low[1] and low < low[2])) and low < low[-1] and low < low[-2], low, 0);

plot upfractal = if( isupfractal, isupfractal + (15 * tickSize()), double.nan);

plot downfractal = if( isdownfractal, isdownfractal – (15 * tickSize()), double.nan);

# This business with the tickSize() function is basically putting the arrow further away
# from the bar so that the fractal is easier to read

plot histogramFill = PTO;
histoGramFill.SetPaintingStrategy(paintingStrategy.Histogram);
histoGramFill.SetDefaultColor(color.green);
histoGramFill.SetLineWeight(3);

plot zeroCross = if PTO >= 0 then 0 else double.nan;
zeroCross.SetPaintingStrategy(paintingStrategy.points);

Here is a modification that I made that plots a DOT on the zero line for any time the TRIN is ABOVE 0 “bullish” and no dot when not plotted. The way this is to be used is NOT as a trade system but as a way of saying OKAY should I be more or less bullish. You have to wait until next bar is plotted for confirmation. So basically you want to look for shorts when no dots and buys when dots.

plot zeroCross = if PTO >= 0 then 0 else double.nan;
zeroCross.SetPaintingStrategy(paintingStrategy.points);

Put this on base study (behind graph) and hide everything else except zero line.

http://stockcharts.com/school/doku.php?id=chart_school:technical_indicators:introduction_to_mark#mcclellan_summation_