* Interface to sequences of expression pairs. */
/*
- * GiNaC Copyright (C) 1999-2001 Johannes Gutenberg University Mainz, Germany
+ * GiNaC Copyright (C) 1999-2002 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
#include <vector>
#include <list>
-
// CINT needs <algorithm> to work properly with <vector> and <list>
#include <algorithm>
#include "expair.h"
-#ifndef NO_NAMESPACE_GINAC
namespace GiNaC {
-#endif // ndef NO_NAMESPACE_GINAC
-
-//#define EXPAIRSEQ_USE_HASHTAB
-
-typedef std::vector<expair> epvector;
-typedef epvector::iterator epviter;
-
-inline void iter_swap(epvector::iterator it1, epvector::iterator it2)
-{
- (*it1).rest.swap((*it2).rest);
- (*it1).coeff.swap((*it2).coeff);
-}
-typedef epvector::iterator epp;
-typedef std::list<epp> epplist;
-typedef std::vector<epplist> epplistvector;
+/** 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
+typedef std::vector<epplist> epplistvector; ///< vector of epplist
/** A sequence of class expair.
* This is used for time-critical classes like sums and products of terms
* since handling a list of coeff and rest is much faster than handling a
- * list of products or powers, respectively. (Incidentally, Maple does it
- * the same way.) */
+ * list of products or powers, respectively. (Not incidentally, Maple does it
+ * the same way, maybe others too.) The semantics is (at least) twofold:
+ * one for addition and one for multiplication and several methods have to
+ * be overridden by derived classes to reflect the change in semantics.
+ * However, most functionality turns out to be shared between addition and
+ * multiplication, which is the reason why there is this base class. */
class expairseq : public basic
{
GINAC_DECLARE_REGISTERED_CLASS_NO_CTORS(expairseq, basic)
// member functions
- // default constructor, destructor, copy constructor assignment operator and helpers
+ // default ctor, dtor, copy ctor, assignment operator and helpers
public:
expairseq() : basic(TINFO_expairseq)
-#ifdef EXPAIRSEQ_USE_HASHTAB
+#if EXPAIRSEQ_USE_HASHTAB
, hashtabsize(0)
-#endif // def EXPAIRSEQ_USE_HASHTAB
- {
- }
- ~expairseq()
- {
- destroy(0);
- }
+#endif // EXPAIRSEQ_USE_HASHTAB
+ { }
+ ~expairseq() { destroy(false); }
expairseq(const expairseq & other);
const expairseq & operator=(const expairseq & other);
protected:
void copy(const expairseq & other);
- void destroy(bool call_parent)
- {
- if (call_parent) basic::destroy(call_parent);
- };
-
- // other constructors
+ void destroy(bool call_parent);
+ // other ctors
public:
expairseq(const ex & lh, const ex & rh);
expairseq(const exvector & v);
expairseq(const epvector & v, const ex & oc);
expairseq(epvector * vp, const ex & oc); // vp will be deleted
-
- // functions overriding virtual functions from bases classes
+
+ // functions overriding virtual functions from base classes
public:
basic * duplicate() const;
- void print(std::ostream & os, unsigned upper_precedence=0) const;
- void printraw(std::ostream & os) const;
- void printtree(std::ostream & os, unsigned indent) const;
+ void print(const print_context & c, unsigned level = 0) const;
+ unsigned precedence(void) const {return 10;}
bool info(unsigned inf) const;
unsigned nops() const;
ex op(int i) const;
ex & let_op(int i);
+ ex map(map_function & f) const;
ex eval(int level=0) const;
- ex evalf(int level=0) const;
- ex normal(lst &sym_lst, lst &repl_lst, int level=0) const;
ex to_rational(lst &repl_lst) const;
- ex subs(const lst & ls, const lst & lr) const;
+ bool match(const ex & pattern, lst & repl_lst) const;
+ ex subs(const lst & ls, const lst & lr, bool no_pattern = false) const;
protected:
- ex derivative(const symbol & s) const;
int compare_same_type(const basic & other) const;
bool is_equal_same_type(const basic & other) const;
unsigned return_type(void) const;
unsigned calchash(void) const;
ex expand(unsigned options=0) const;
-
+
// new virtual functions which can be overridden by derived classes
protected:
virtual ex thisexpairseq(const epvector & v, const ex & oc) const;
virtual ex thisexpairseq(epvector * vp, const ex & oc) const;
- virtual void printseq(std::ostream & os, char delim,
+ virtual void printseq(const print_context & c, char delim,
unsigned this_precedence,
unsigned upper_precedence) const;
- virtual void printpair(std::ostream & os, const expair & p,
+ virtual void printpair(const print_context & c, const expair & p,
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,
void construct_from_epvector(const epvector & v);
void make_flat(const exvector & v);
void make_flat(const epvector & v);
- epvector * bubblesort(epvector::iterator itbegin, epvector::iterator itend);
- epvector * mergesort(epvector::iterator itbegin, epvector::iterator itend);
void canonicalize(void);
void combine_same_terms_sorted_seq(void);
-#ifdef EXPAIRSEQ_USE_HASHTAB
+#if EXPAIRSEQ_USE_HASHTAB
void combine_same_terms(void);
unsigned calc_hashtabsize(unsigned sz) const;
unsigned calc_hashindex(const ex & e) const;
void remove_hashtab_entry(epvector::const_iterator element);
void move_hashtab_entry(epvector::const_iterator oldpos,
epvector::iterator newpos);
- void sorted_insert(epplist & eppl, epp elem);
+ 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,
bool has_coeff_0(void) const;
void add_numerics_to_hashtab(epvector::iterator first_numeric,
epvector::const_iterator last_non_zero);
-#endif // def EXPAIRSEQ_USE_HASHTAB
+#endif // EXPAIRSEQ_USE_HASHTAB
bool is_canonical() const;
epvector * expandchildren(unsigned options) const;
epvector * evalchildren(int level) const;
- epvector evalfchildren(int level) const;
- epvector normalchildren(int level) const;
- epvector diffchildren(const symbol & s) const;
- epvector * subschildren(const lst & ls, const lst & lr) const;
+ epvector * subschildren(const lst & ls, const lst & lr, bool no_pattern = false) const;
// member variables
protected:
epvector seq;
ex overall_coeff;
- static unsigned precedence;
-#ifdef EXPAIRSEQ_USE_HASHTAB
+#if EXPAIRSEQ_USE_HASHTAB
epplistvector hashtab;
unsigned hashtabsize;
unsigned hashmask;
static unsigned maxhashtabsize;
static unsigned minhashtabsize;
static unsigned hashtabfactor;
-#endif // def EXPAIRSEQ_USE_HASHTAB
+#endif // EXPAIRSEQ_USE_HASHTAB
};
// utility functions
-inline const expairseq &ex_to_expairseq(const ex &e)
+
+/** Specialization of is_exactly_a<expairseq>(obj) for expairseq objects. */
+template<> inline bool is_exactly_a<expairseq>(const basic & obj)
{
- return static_cast<const expairseq &>(*e.bp);
+ return obj.tinfo()==TINFO_expairseq;
}
-#ifndef NO_NAMESPACE_GINAC
} // namespace GiNaC
-#endif // ndef NO_NAMESPACE_GINAC
#endif // ndef __GINAC_EXPAIRSEQ_H__
git://www.ginac.de / ginac.git / blobdiff