*! version 1.0.0  20nov1996 STB-34 sts12
program define wntestf
	version 5.0

	local varlist	"req ex min(1) max(1)"
	local in	"opt"
	local if	"opt"
	local options	"Level(integer $S_level) SAving(string) t(string)"
	local options   "`options' noGRaph T1title(string) XLAbel(string)"
	local options   "`options'  YLAbel(string) *"

	parse "`*'"

	tempvar touse
	mark `touse' `if' `in'
	markout `touse' `varlist'

	local samp "if `touse'==1"

	if "`t'" != "" {
		local targ ", t(`t')"
	}

  if `level'<10 | `level'>99 {
                local level 95
        }


	quietly {

		_crcchkt `samp' `targ'  

		* Sample is set and t variable verified to be good

		replace `touse' = . if `touse' == 0
		sort `touse' `t'

		* Data now sorted so that sample is at top of dataset

		tempvar x
		gen double `x'=`varlist' `samp'    

		* Uncomment when jwh fixes fft
		*tempvar xr xi

		count `samp'     
		local N=_result(1)

		local samp "in 1/`N'"

		local n1=int(`N'/2)+1

		tempvar w 
		gen double `w'=((_n-1)/`N') in 1/`n1'

		* Problem with internal fft -- will be fixed
		* noi di in red "fft `x', gen(`xr' `xi')"

		* Fix this!!  replace with tempvars when jwh fixes fft routine

		capture query born
		if _rc {
			local hasfix 0
		}
		else {
			* Hope that query born saves date somewhere
			local hasfix 1
		}
		
		local hasfix 0

		if `hasfix' {
			tempvar xr xi
			fft `x' `samp', gen(`xr' `xi')
		}
		else {
			capture drop _xr _xi
			fft `x' `samp', gen(_xr _xi)
			local xr "_xr"
			local xi "_xi"
		}

		replace `xr'=0 in 1
		replace `xi'=0 in 1
		replace `xr'=sum(`xr'*`xr'+`xi'*`xi')
		local    ss =`xr' in `n1'
		replace `xr'=`xr'/`ss'



	}
	label var `xr' "cumulative periodogram"
	label var `w' "frequency"

	qui replace `x'=.
	qui replace `x'=abs(`xr'-2*`w') in 1/`n1'
	qui sum `x'
	local stat=sqrt(`n1')*_result(6)
	qui bartcdf `stat'
	local pvalue=1-$S_1

	* Add test in here and save results in the S_# macros

	if "`graph'" == "" {

		if "`saving'"!="" {
			local sarg ", saving(`saving')"
		}

		gph open `sarg'

		if "`t1title'"=="" {
			local t1title "Cumulative Periodogram White Noise Test"
		}

		if "`xlabel'"=="" {
			local xlabel "0,.1,.2,.3,.4,.5"
		}

		if "`ylabel'"=="" {
			local ylabel "0,.2,.4,.6,.8,1"
		}



		graph `xr' `w', s(i) xlab(`xlabel') ylab(`ylabel') `options' /*
			*/  border t1("`t1title'")
		gphsave

		gph pen 2

		tempvar size
		gen int `size' = 175
		gphdt vpoint `xr' `w' `size' `samp'

		gphdt text 1 .25 0 0 $S_3
		gph pen 1

		gph pen 3
		gphdt li 0 0 1 .5

		local lev=`level'/100
		bartq `lev'
				
		local sq1=$S_2/sqrt(`n1')
		local sq2=1.-`sq1'
		local sq3=`sq2'/2
		local sq4=`sq1'/2

		if "$S_OS" == "Unix" {
			gph pen 5
		}
		else    gph pen 4

		gphdt line `sq1' 0 1 `sq3' 
		gphdt line 0 `sq4' `sq2'  .5 

		gph close
	}

	* Remove this when jwh fixes fft
	capture drop _xr _xi

	global S_1=`stat'
	global S_2=`pvalue'

end