function Total_defects(f, verbose) {
  return \
  	defects(f,"requirements","r", verbose) + \
	defects(f,"design",      "d", verbose) + \
	defects(f,"coding",      "c", verbose)
}
function defects(f,what,area,verbose,  introduced,percentRemoved) {
  introduced     = defectsIntroduced1(f,what,area);
  percentRemoved = defectsRemovedRatio(f,what,area);
  if (verbose)
	  print "f",f,"area",area,"intro",introduced,
			"p",percentRemoved, "removed",percentRemoved*introduced
  return percentRemoved*introduced;
}
function defectsIntroduced1(f,what,area) {
	return areaWeight(area)*Ksloc(f)^defectsB(area) * defectsIntroduced2(f,area);
}
BEGIN                     { string2pairs(_DefectsB,"r,10,d,20,c,30") }
function areaWeight(area) { return _DefectsB[area] }
function defectsB(area)   { return 1}

function defectsIntroduced2(f,area,    temp,out,x,s,n) {
	out=1;
	for(x in Type)  {
		s    = cachedSlot(f,x)
		n    = Factors2Numbers[s]
		temp = Coqual[area,n,x];
		out *= temp
	}
	return out;
}
function defectsRemovedRatio(f,what,area, auto,review,tool) {
	auto   = drf(f,"automated_analysis",area);
	review = drf(f,"peer_reviews",area);
	tool   = drf(f,"execution_testing_and_tools",area);
	return (1 - auto)*(1 - review)*(1 - tool);
}
function drf(f,x,area,n,  out) {
	n= Factors2Numbers[cachedSlot(f,x)]
	out= Drf[area, n,x]
	return out
}