*! version 0.1.0 3/8/94         gr16: STB-23
program define condraw
   version 3.1
   local varlist "req ex min(3) max(3)"
   local options /*
   */ "`options' Hull(int 1) Group(str) GRno(int 0) Dr(str) Vid(str)"    
   parse "`*'"
   parse "`varlist'",parse(" ")
   local hullno "`hull'"
   local grnum "`grno'"
   if ("`group'"=="") {
      tempvar all
      mac def _group `all'
      quietly gen byte `group'=1
   }
   if ("`dr'"=="") {
      mac def _dr "dr"
   }
   if ("`vid'"=="") {
      mac def _vid "hv"
   }

   tempvar touse
   mark `touse'
   markout `touse' `varlist'
   quietly count if `3'==`hullno'
   if _result(1)==0 {
      di in red "Requested hull exceeds the maximum number of" 
      di in red "hulls assigned for any group"
      quietly summarize `3'
      di in red "There are only " _result(6)   " hulls assigned"
      exit
   }                 
   if (`grnum'>0) {
      local fs=`grnum'
      local ls=`grnum'
   }
   else {
      quietly summarize `group'
      local fs=_result(5)
      local ls=_result(6)
   }
   tempvar mk loc
   quietly gen byte `loc'=.
   quietly gen `mk'=0
   local uj=0
   local gm=" `2'"
   local cm="c(."
   local sm="s("
   local vm="Variables: "
   tempvar theta marker dx dy
   quietly gen byte `marker'=.
   quietly gen `theta'=-1e37
   quietly gen `dx'=.
   quietly gen `dy'=.
   quietly gen `dr'=0
   quietly while `fs'<=`ls' {
      local flag=1
      while `fs'<=`ls' & `flag'==1 {
         replace `mk'=-1e37 if `3'==`hullno' & `group'==`fs'
         sort `mk' `group'
         count if `group'==`fs' & `mk'!=0
         if _result(1)==0 {
            local flag=1
            if `fs'==real("`grno'") {
               n di in red "No hull points for group " `grno'
               n di in red "drop dr and try another group or hull"
               exit
            }
         }
         else {
            local fs=`fs'-1
            local flag=0
         }
         local fs=`fs'+1
      }
      local ui=1
      local uj=_result(1)
      sort `2' `1' in `ui'/`uj'
      replace `marker'=1 in `ui'/`uj'
      replace `marker'=2 in `ui'
      expand `marker'
      replace `marker'=0 in `ui'
      replace `dr'=1 if `marker'==2
      sort `marker' `mk'
      local uk=`uj'+1
      local i=`ui'
      local j=`i'+1
      while `marker'[`i'] !=2 {
         replace `marker'=0 in `i'
         replace `dx'=`1'-`1'[`i'] in `j'/`uk'
         replace `dy'=`2'-`2'[`i'] in `j'/`uk'
         replace `theta'=0 in `j'/`uk'
         replace `theta'=. if `dx'==0 & `dy'==0 in `j'/`uk'
         replace `theta'=`dy' /(abs(`dx') + abs(`dy')) if `dy'!=0 in `j'/`uk'
         replace `theta'=2-`theta' if `dx'<0 in `j'/`uk'
         replace `theta'=4+`theta' if `dx'>=0 & `dy'<0 in `j'/`uk'
         replace `theta'=`theta'-2 in `j'/`uk'
         replace `theta'=. if `theta'<`theta'[`i'] in `j'/`uk'
         sort `theta' in `j'/`uk'
         local i=`j'
         local j=`j'+1
      }
      di "`vid'"
      local var="`vid'"+"`fs'"
      tempvar `var'
      gen `var'=.
      replace `var'=`2' in `ui'/`uk'
      if `fs'!=`ls' {
         local gm="`gm'"+ " `var'"
         local cm="`cm'"+"l"
         local sm="`sm'"+"[`group']"
         local vm="`vm'"+" `var'"
      }
      else {
         local gm="`gm'"+" `var'"+ " `1'"
         local cm="`cm'"+"l)"
         local sm="`sm'"+"[`group'])"
         local vm="`vm'"+" `var'"+" were created"
      }  
      replace `marker'=. in `ui'/`uk'
      replace `mk'=. in `ui'/`uk'
      replace `loc'=_n in `ui'/`uk'
      local uj=`uj'+1
      local fs=`fs'+1
   }
   sort `3' `group' `loc'
   graph `gm',`cm' `sm'
   if ("`group'"=="all") {
      quietly drop `group'
   }
   di "`vm'"
   di "You can redraw the graph with the command:"
   di in green "graph ""`gm'"", ""`cm'"" ""`sm'"
   di "You can now change the graph options, add titles, save, etc."
   di "To use the same data set to generate a different graph or to eliminate"
   di "all the created variables use the following sequence of commands"
   di "(making sure to follow the order given):"
   di in green ". drop if " "`dr'""==1"
   di in green ". drop " "`dr'"" " "`vid'""*"
end                        
exit