*! version 1.0.0 STB-34 sts12
program define bartq
	version 5.0

	local u `1'

	if `u' <= 0.0 | `u' >= 1.0 {
		noi di in red "argument of bartq must be in (0,1)"
		exit 198
	}

	local left=.3
	local right=2.
	local middle=1.15
	local eps=.0001

	local i=1
	while `i' <= 100 {

		bartcdf `middle'
*		di $S_1 " " `left' " " `middle' " " `right'

		if $S_1 < `u' {	local left=`middle'}
		else { local right=`middle'}

		local del=`right'-`left'

		if `del' < `eps' {
*			di `i'
			local i=101
			global S_2=`middle'
		}			
		else {
			local i=`i'+1
			local middle=(`left'+`right')/2.
		}
						
	}

*	di $S_2 " " $S_1

end