Remove unfinished code for hash table-based expairseq.

[ginac.git] / ginac / expairseq.h

diff --git a/ginac/expairseq.h b/ginac/expairseq.h
index 753dceca2181ef8ee4fe4e4bbcae866fe8690940..6e98bbfcc70572ae56aa1b55a88f8380dc858714 100644 (file)
--- a/ginac/expairseq.h
+++ b/ginac/expairseq.h
@@ -3,7 +3,7 @@
  *  Interface to sequences of expression pairs. */
 
 /*
- *  GiNaC Copyright (C) 1999-2014 Johannes Gutenberg University Mainz, Germany
+ *  GiNaC Copyright (C) 1999-2015 Johannes Gutenberg University Mainz, Germany
  *
  *  This program is free software; you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License as published by
@@ -34,17 +34,6 @@
 
 namespace GiNaC {
 
-/** Using hash tables can potentially enhance the asymptotic behaviour of
- *  combining n terms into one large sum (or n terms into one large product)
- *  from O(n*log(n)) to about O(n).  There are, however, several drawbacks.
- *  The constant in front of O(n) is quite large, when copying such an object
- *  one also has to copy the has table, comparison is quite expensive because
- *  there is no ordering any more, it doesn't help at all when combining two
- *  expairseqs because due to the presorted nature the behaviour would be
- *  O(n) anyways, the code is quite messy, etc, etc.  The code is here as
- *  an example for following generations to tinker with. */
-#define EXPAIRSEQ_USE_HASHTAB 0
-
 typedef std::vector<expair> epvector;       ///< expair-vector
 typedef epvector::iterator epp;             ///< expair-vector pointer
 typedef std::list<epp> epplist;             ///< list of expair-vector pointers
@@ -133,27 +122,6 @@ protected:
        void make_flat(const epvector & v, bool do_index_renaming = false);
        void canonicalize();
        void combine_same_terms_sorted_seq();
-#if EXPAIRSEQ_USE_HASHTAB
-       void combine_same_terms();
-       unsigned calc_hashtabsize(unsigned sz) const;
-       unsigned calc_hashindex(const ex & e) const;
-       void shrink_hashtab();
-       void remove_hashtab_entry(epvector::const_iterator element);
-       void move_hashtab_entry(epvector::const_iterator oldpos,
-                               epvector::iterator newpos);
-       void sorted_insert(epplist & eppl, epvector::const_iterator elem);
-       void build_hashtab_and_combine(epvector::iterator & first_numeric,
-                                      epvector::iterator & last_non_zero,
-                                      vector<bool> & touched,
-                                      unsigned & number_of_zeroes);
-       void drop_coeff_0_terms(epvector::iterator & first_numeric,
-                               epvector::iterator & last_non_zero,
-                               vector<bool> & touched,
-                               unsigned & number_of_zeroes);
-       bool has_coeff_0() const;
-       void add_numerics_to_hashtab(epvector::iterator first_numeric,
-                                    epvector::const_iterator last_non_zero);
-#endif // EXPAIRSEQ_USE_HASHTAB
        bool is_canonical() const;
        std::auto_ptr<epvector> expandchildren(unsigned options) const;
        std::auto_ptr<epvector> evalchildren(int level) const;
@@ -164,20 +132,12 @@ protected:
 protected:
        epvector seq;
        ex overall_coeff;
-#if EXPAIRSEQ_USE_HASHTAB
-       epplistvector hashtab;
-       unsigned hashtabsize;
-       unsigned hashmask;
-       static unsigned maxhashtabsize;
-       static unsigned minhashtabsize;
-       static unsigned hashtabfactor;
-#endif // EXPAIRSEQ_USE_HASHTAB
 };
 
 /** Class to handle the renaming of dummy indices. It holds a vector of
- *  indices that are being used in the expression so-far. If the same
+ *  indices that are being used in the expression so far. If the same
  *  index occurs again as a dummy index in a factor, it is to be renamed.
- *  Unless dummy index renaming was swichted of, of course ;-) . */
+ *  Unless dummy index renaming was switched off, of course ;-) . */
 class make_flat_inserter
 {
        public: