*! version 1.1.1  01/08/94
program define nptri
	version 3.1
	parse "`*'", parse(",\ ")

	local r 1 
	local c 1
	local cols .
	while ("`1'"!="" & "`1'"!=",") { 
		if "`1'"=="\" {
			local r = `r' + 1
			if `cols'==. { 
				if (`c'<=2) { 
					di in red "too few columns"
					exit 198
				}
				local cols `c'
			}
			else {
				if (`c'!=`cols') { error 198 }
			}
			local c 1
		}
		else {
			conf integer num `1'
			if `1'<0 { error 411 } 
			local n`r'`c' `1'
			local c = `c' + 1
		}
		mac shift
	}
	if (`c'!=`cols') { error 198 } 
	local cols = `cols' - 1
	local rows = `r' 
			
	local options "REPLACE Midrank *"
	parse "`*'"
	if "`replace'"=="" & _N!=0 { 
		preserve
	}
	capture {
		drop _all
		local obs 1 
		set obs 1 
		gen byte row = . 
		gen byte col = . 
		gen long pop = . 
		local r 1 
		while (`r'<=`rows') { 
			local c 1
			while (`c'<=`cols') { 
				set obs `obs'
				replace row = `r' in l 
				replace col = `c' in l 
				replace pop = `n`r'`c'' in l 
				local obs = `obs' + 1
				local c = `c' + 1 
			}
			local r = `r' + 1
		}
 sort row
 tempvar rtot srt v
 egen `rtot'=sum(pop),by(row)
 sort row
 gen rank=row!=row[_n-1]
 gen `srt'=sum(`rtot'*rank)
 local N = `srt'[_N]
 by row:replace rank=`srt'[1]-(`rtot'-1)/2
	if "`midrank'"!="" {
		sort col
		tempvar ctot sct
	 	egen `ctot'=sum(pop),by(col)
		sort col
		gen z=col!=col[_n-1]
 		gen `sct'=sum(`ctot'*z)
		by col:replace z=`sct'[1]-(`ctot'-1)/2
		replace z=z/`N'
	}
	else 	gen z = col
 gen `v'=sum(z*pop)
 local v1 = `v'[_N]
 replace `v'=sum(z^2*pop)
 local v2 = `v'[_N]
 replace `v'=sum(pop*(`rtot'^2-1))
 local corr = `v'[_N]
 replace `v'=sum(z*pop*(rank-(`N'+1)/2))
 local T_ET = `v'[_N]
 local V = (`N'+1)*(`N'*`v2'-(`v1'^2))/12
 local adj = (1-`corr'/(`N'*(`N'^2-1)))
 local zstat = `T_ET'/sqrt(`V'*`adj')
 local pval = 2*( 1-normprob(abs(`zstat')))
	noisily di in gr "     z  = " in ye %5.2f `zstat' in gr ", chi-squared(1) = " in ye %6.2f `zstat'^2
	noisily di in gr "  P>|z| = " in ye %6.4f `pval'
	global S_1 = `N'
	global S_3 = `zstat'
	global S_4 = `pval'
	}
	if _rc { 
		drop _all
		exit `rc'
	}
end