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Code:
// Chirp cutoff ///////////////////

function run()
{
	BarPeriod = 60;
	MaxBars = 1000;
	LookBack = 100;
	asset(""); // dummy asset
	ColorUp = ColorDn = 0; // don't plot a price curve
	PlotHeight1 = PlotHeight2 = 200;
	PlotWidth = 800;
	set(PLOTNOW);
	
	vars Chirp = series(genSine(5,60));
	int Color = BLACK;
	plot("ChirpBefore",Chirp[0],0,Color);
	if(Chirp[0]>0.5)plot("ChirpAfter",Chirp[0],NEW,Color);
}