
 0.1  first version, two functions "matrix2poly" and "scdd". 

      "matrix2poly" the former is deprecated and should be removed

      "scdd" successfully does conversion between H-representation and
      V-representation (both ways) using real arithmetic (as opposed
      to other two possibilities: integer arithmetic or GNU multiple
      precision arithmetic)

      To do: other arithmetic modes are essential

 0.2  second version, function "matrix2poly" removed.

      functions "d2q", "q2d", "q2q", and "z2q" added -- conversion between
      IEEE floating point and GMP rationals.

      "scdd" now takes GMP rational arguments as well as IEEE reals.

      function "validcdd" -- validates H-representations and V-representations

      functions "validcdd", "makeH", "addH", and "dropH" added --
      construction and adjustment of H-representations

 0.3  many changes

      completely redesigned "cdd objects", now former "linearity" component
      is represented in first column of matrix, and former "representation"
      component is now "representation" attribute of matrix, so "cdd objects"
      are just matrices having a certain form (first column of
      H-representation is zero-or-one valued, first two columns of
      V-representation are zero-or-one valued)

      removed "dropH", replaced "addH" by "addHeq" and "addHin"
      former "dropH" can now just be done by matrix indexing,
      e. g., if "qux" is cdd object, then qux[-3, ] drops row 3.
      added argument "x" to "makeH" so "addHeq" and "addHin" can
      be implemented simply as calls to "makeH"

      function "qmq" added -- subtraction of GMP rationals -- useful
      for exact comparison.

      also completely revised and expanded description in inst/doc/design.tex

 0.4  GPL, Makevars

 0.5  changed name of package from cdd to rcdd per request from Fukuda

 0.6  added maximal, all.intersect

      added convex hull example to scdd (how absurdly simple, how stupid
         of me not to have seen that).

      added qpq, qxq, qdq

 0.6-1  fixed bug in nonred.c, using uninitialized variables, found by
        valgrind

      cleaned up qoq.c, removed unnecessary initialization mpq_init
      always initializes to zero

      added autoconf

 0.6-2  autoconf changes

          * changed LIBS to LDFLAGS following autoconf conventions

      scdd (and scdd_f) change, H-representation now allowed to be
      matrix with zero rows (represents the whole space).  Important
      that this be allowed because scdd can produce such a representation
      (when the whole space is the convex polytope in question).
      OTOH an empty V-representation (representing the empty set)
      is NOT allowed because (1) scdd does not produce such and (2)
      error exits when given such.

      fixed z2q so it preserves attributes (expecially "dim"), just like
      the qoq functions.

      added rudimentary vignette

      modified error messages as per Writing R Extensions, Sec 1.8

 0.6-3  autoconf changes, now checks for libraries

