Thu 10 Jun 2021 : added the exec_dir attribute to ad.gpr.

Tue 8 Jun 2021 : defined ad.gpr to build the test procedures.

Fri 21 Dec 2018 : new type system in generic_polynomial_vectors to
  hold maximal exponents, which extended random_polynomial_vectors,
  all *polynomial_vectors_io, system_vector_convertors, and the
  test procedures ts_polvec.adb and ts_sys2vec.adb.
  To generic_polynomial_vectors, added speel() procedure to use the cached
  power tables for evaluation and differentiation.

Thu 20 Dec 2018 : modified random_monomials to retry if the degree of the
  generated monomial equals zero.  Set verbose flag in ts_monom.adb.
  Made similar modifications to random_monomial_vectors.a* and
  random_polynomial_vectors.adb.  Added the computation of the largest
  exponents to generic_monomial_vectors, updated the *_io.adb packages.
  Added maximal exponents and power table to the data structure record
  of a polynomial in generic_monomial_vectors, which changed their *io.adb.
  Updated generic_monomials, ts_monvec, random_monomial_vectors.adb,
  and system_vector_convertors.adb.  Distinguished case with m.n_base = 0
  in generic_monomial_vectors, added speel_without_cache for bug fix...
  In generic_monomial_vectors.adb, fixed bug in Largest_Exponents.

Wed 19 Dec 2018 : fixed bug in system_vector_convertors, added a function
  to check on the constant term, fixed bug in generic_polynomial_vectors.adb,
  updated the ts_sys2vec.adb to compute norms of the differences.
  Added power table code to generic_monomials for general evaluation,
  which changed the instantiations *complex_monomials.ads and also
  added more output to the *complex_monomials_io.adb, with better tests
  in ts_monvec.adb.  The generic_monomial_vectors.ads changed and all its
  instantiations in *monomial_vectors.ads, improved ts_monvec.adb.
  The generic_polynomial_vectors.ads changed and so did all its
  instantiations in *polynomial_vectors.ads, improved ts_polvec.adb.
  Added degree() functions to generic_monomial_vectors and updated
  {standard,dobldobl,quaddobl}_monomial_vectors_io.adb.

Tue 18 Dec 2018 : added a polynomial type to generic_monomial_vectors,
  which changed {standard,dobldobl,quaddobl}_monomial_vectors_io.
  This caused changes in generic_polynomial_vectors and ts_polvec.
  All generators for random instances, the random_monomials, the
  random_monomial_vectors, and random_polynomial_vectors were modified.
  Extended the evaluation and differentiation in generic_monomials
  and generic_monomial_vectors, tested by ts_monvec.adb.
  Added differentiation to generic_polynomial_vectors, tested by ts_polvec.
  Added a Create() function to generic_monomials.
  New package system_vector_convertors tested by ts_sys2vec.adb.

Mon 17 Dec 2018 : added the straightforward evaluation functions to
  generic_monomials, generic_monomial_vectors, generic_polynomial_vectors,
  tested by ts_monom, ts_monvec, and ts_polvec.
  Modified generic_monomials.adb and generic_monomial_vectors.adb
  so the Eval() functions perform the multiplications in place.
  Added the straighforward differentiation and Speelpenning algorithm
  for a product of variables to generic_monomials, tested by ts_monom.adb.

Sun 16 Dec 2018 : moved the put procedures from ts_monom into separate i/o,
  into the packages {standard,dobldobl,quaddobl}_monomials_io.
  New package random_monomials with the code from ts_monom.adb.
  Defined vectors of monomials in generic_monomial_vectors and instantiated
  {standard,dobldobl,quaddobl}_monomial_vectors, with output in the
  corresponding _io packages, defined random_monomial_vectors, tested
  by ts_monvec.adb.  Defined the analogue polynomial_vectors packages.

Sat 15 Dec 2018 : new package generic_monomials, instantiated for double,
  double double and quad double complex coefficients, tested by ts_monom.
