set verbose off

function bundle discrete_check (const list L)
   list dlist
   matrix nvals = {}
   bundle b
   loop i=1..nelem(L)
      b = getinfo(L[i])
      if b.discrete
         dlist += L[i]
         nvals ~= nelem(values(L[i]))
      endif
   endloop
   return _(dlist, nvals)
end function

open mroz87.gdt --quiet
list L = dataset
bundle b = discrete_check(L)
list print b.dlist