* Draw dominance-diversity curve
program define domdiver
version 2.1
capture drop h_1
mac def _varlist "req ex "
mac def _if "optional"
mac def _options "*"
parse "%_*"
parse "%_varlist", parse(" ")
macro define a "l1(Abundance [Log Scale])"
macro define b "b2(Species Rank)"
macro define c "b1(Dominance-Diversity Curve)"
  mac def x "jk"
  mac def y "jk"
capture confirm number %x
capture confirm number %y
quietly{  gen h_1=-%_1
      sort h_1
      replace h_1=_n }
mac def n=1
while %_1[%n+1]~=.  {
 mac def n=%n+1 
     }
di " "
di "  DOMDIVER draws a dominance-diversity curve."
di " "
di "To control scale of the X-axis, enter a maximum value (must be >" %n ")"
di "    OR  Press <Enter> to let STATA select X-axis scale."
di "Enter X-axis maximum (or press <Enter>)..." _r(x)
di " "
di "To control scale of the Y-axis, enter a maximum value (>" %_1[1] ")"
di "    OR  Press <Enter> to let STATA select Y-axis scale."
di "Enter Y-axis maximum (or press <Enter>)..." _r(y)
if "%x"=="" {mac def x=%n  }
if "%y"=="" {mac def y =%_1[1]  }
di " "
di "Enter a title to label this graph,"
di "    OR press <Enter> to use " in red "   %_1  " in white " as a label."
di "Title..." _r(xn)
di " "
if "%xn"=="" {mac def xn "%_1"}
    mac def xn "t2(%xn)"
gr %_1 h_1, c(l) xscale(1,%x) yscale(1,%y) ylog ylab xlab %a %b %c %xn %_options
if "%_options"=="" {
di " "
di "   To print this graph, run domdiver again specifying a filename,"
di " e.g.,       domdiver %_1, saving(jt6)"}
      drop h_1
end