X-Git-Url: https://www.ginac.de/ginac.git//ginac.git?p=ginac.git;a=blobdiff_plain;f=ginac%2Fexpairseq.h;h=6e98bbfcc70572ae56aa1b55a88f8380dc858714;hp=4cfc057961e53d9356c8e811092f19de04f249b0;hb=c532971f9e99886781437912ae1655719284ac2f;hpb=80ceed0c855ea06ff5acd9375ad2e0c5ca386373 diff --git a/ginac/expairseq.h b/ginac/expairseq.h index 4cfc0579..6e98bbfc 100644 --- a/ginac/expairseq.h +++ b/ginac/expairseq.h @@ -3,7 +3,7 @@ * Interface to sequences of expression pairs. */ /* - * GiNaC Copyright (C) 1999-2006 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 @@ -20,30 +20,20 @@ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ -#ifndef __GINAC_EXPAIRSEQ_H__ -#define __GINAC_EXPAIRSEQ_H__ +#ifndef GINAC_EXPAIRSEQ_H +#define GINAC_EXPAIRSEQ_H + +#include "expair.h" +#include "indexed.h" -#include -#include -#include // CINT needs to work properly with and #include - -#include "expair.h" +#include +#include +#include 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 epvector; ///< expair-vector typedef epvector::iterator epp; ///< expair-vector pointer typedef std::list epplist; ///< list of expair-vector pointers @@ -70,8 +60,8 @@ class expairseq : public basic public: expairseq(const ex & lh, const ex & rh); expairseq(const exvector & v); - expairseq(const epvector & v, const ex & oc); - expairseq(std::auto_ptr, const ex & oc); + expairseq(const epvector & v, const ex & oc, bool do_index_renaming = false); + expairseq(std::auto_ptr, const ex & oc, bool do_index_renaming = false); // functions overriding virtual functions from base classes public: @@ -83,10 +73,12 @@ public: ex eval(int level=0) const; ex to_rational(exmap & repl) const; ex to_polynomial(exmap & repl) const; - bool match(const ex & pattern, lst & repl_lst) const; + bool match(const ex & pattern, exmap& repl_lst) const; ex subs(const exmap & m, unsigned options = 0) const; ex conjugate() const; - bool is_polynomial(const ex & var) const; + + void archive(archive_node& n) const; + void read_archive(const archive_node& n, lst& syms); protected: bool is_equal_same_type(const basic & other) const; unsigned return_type() const; @@ -95,8 +87,8 @@ protected: // new virtual functions which can be overridden by derived classes protected: - virtual ex thisexpairseq(const epvector & v, const ex & oc) const; - virtual ex thisexpairseq(std::auto_ptr vp, const ex & oc) const; + virtual ex thisexpairseq(const epvector & v, const ex & oc, bool do_index_renaming = false) const; + virtual ex thisexpairseq(std::auto_ptr vp, const ex & oc, bool do_index_renaming = false) const; virtual void printseq(const print_context & c, char delim, unsigned this_precedence, unsigned upper_precedence) const; @@ -104,9 +96,9 @@ protected: unsigned upper_precedence) const; virtual expair split_ex_to_pair(const ex & e) const; virtual expair combine_ex_with_coeff_to_pair(const ex & e, - const ex & c) const; + const ex & c) const; virtual expair combine_pair_with_coeff_to_pair(const expair & p, - const ex & c) const; + const ex & c) const; virtual ex recombine_pair_to_ex(const expair & p) const; virtual bool expair_needs_further_processing(epp it); virtual ex default_overall_coeff() const; @@ -125,32 +117,11 @@ protected: void construct_from_expairseq_ex(const expairseq & s, const ex & e); void construct_from_exvector(const exvector & v); - void construct_from_epvector(const epvector & v); + void construct_from_epvector(const epvector & v, bool do_index_renaming = false); void make_flat(const exvector & v); - void make_flat(const epvector & v); + 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 & touched, - unsigned & number_of_zeroes); - void drop_coeff_0_terms(epvector::iterator & first_numeric, - epvector::iterator & last_non_zero, - vector & 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 expandchildren(unsigned options) const; std::auto_ptr evalchildren(int level) const; @@ -161,16 +132,62 @@ 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 + * index occurs again as a dummy index in a factor, it is to be renamed. + * Unless dummy index renaming was switched off, of course ;-) . */ +class make_flat_inserter +{ + public: + make_flat_inserter(const epvector &epv, bool b): do_renaming(b) + { + if (!do_renaming) + return; + for (epvector::const_iterator i=epv.begin(); i!=epv.end(); ++i) + if(are_ex_trivially_equal(i->coeff, 1)) + combine_indices(i->rest.get_free_indices()); + } + make_flat_inserter(const exvector &v, bool b): do_renaming(b) + { + if (!do_renaming) + return; + for (exvector::const_iterator i=v.begin(); i!=v.end(); ++i) + combine_indices(i->get_free_indices()); + } + ex handle_factor(const ex &x, const ex &coeff) + { + if (!do_renaming) + return x; + exvector dummies_of_factor; + if (is_a(coeff) && coeff.is_equal(GiNaC::numeric(1))) + dummies_of_factor = get_all_dummy_indices_safely(x); + else if (is_a(coeff) && coeff.is_equal(GiNaC::numeric(2))) + dummies_of_factor = x.get_free_indices(); + else + return x; + if (dummies_of_factor.size() == 0) + return x; + sort(dummies_of_factor.begin(), dummies_of_factor.end(), ex_is_less()); + ex new_factor = rename_dummy_indices_uniquely(used_indices, + dummies_of_factor, x); + combine_indices(dummies_of_factor); + return new_factor; + } + private: + void combine_indices(const exvector &dummies_of_factor) + { + exvector new_dummy_indices; + set_union(used_indices.begin(), used_indices.end(), + dummies_of_factor.begin(), dummies_of_factor.end(), + std::back_insert_iterator(new_dummy_indices), ex_is_less()); + used_indices.swap(new_dummy_indices); + } + bool do_renaming; + exvector used_indices; }; } // namespace GiNaC -#endif // ndef __GINAC_EXPAIRSEQ_H__ +#endif // ndef GINAC_EXPAIRSEQ_H