*! version 1.0.0  26Nov95                               (STB-29: ip11)
program define s_no
   version 4.0
   local options "DROP Gap(integer 1) High(integer 32766) Numeric"
   parse "`*'"
   local class "macro"
   if "`numeric'" != "" { local class "scalar" }
   if "`drop'" == "" { local drop "list" }
   local i = 1
   local j = 0
   while (`j' < `gap') & (`i' <= `high') {
      capture `class' list S_`i'
      if _rc & "`numeric'" != "" {
         if "`class'" == "scalar" { local class "matrix" }
         else { local class "scalar" }
         capture `class' list S_`i'
      }
      if _rc { local j = `j' + 1 }
      else {
         `class' `drop' S_`i'
         local j = 0
      }
      local i = `i' + 1
   }
end