3 * Interface to GiNaC's symbolic objects. */
6 * GiNaC Copyright (C) 1999-2001 Johannes Gutenberg University Mainz, Germany
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
23 #ifndef __GINAC_SYMBOL_H__
24 #define __GINAC_SYMBOL_H__
32 /** Basic CAS symbol. It has a name because it must know how to output itself.
33 * It may be assigned an expression, but this feature is only intended for
34 * programs like 'ginsh' that want to associate symbols with expressions.
35 * If you want to replace symbols by expressions in your code, you should
36 * use ex::subs() or use objects of class ex instead of class symbol in the
38 class symbol : public basic
40 GINAC_DECLARE_REGISTERED_CLASS_NO_CTORS(symbol, basic)
44 /** Symbols as keys to expressions - this is deprecated. */
45 class assigned_ex_info {
47 assigned_ex_info(); ///< Default ctor
48 bool is_assigned; ///< True if there is an expression assigned
49 ex assigned_expression; ///< The actual expression
50 unsigned refcount; ///< Reference counter
55 // default ctor, dtor, copy ctor assignment operator and helpers
60 /*debugmsg("symbol dtor", LOGLEVEL_DESTRUCT);*/
63 symbol(const symbol & other);
65 void copy(const symbol & other);
66 void destroy(bool call_parent);
70 explicit symbol(const std::string & initname);
71 explicit symbol(const std::string & initname, const std::string & texname);
73 // functions overriding virtual functions from base classes
75 basic * duplicate() const;
76 void print(const print_context & c, unsigned level = 0) const;
77 bool info(unsigned inf) const;
78 ex expand(unsigned options = 0) const;
79 bool has(const ex & other) const;
80 int degree(const ex & s) const;
81 int ldegree(const ex & s) const;
82 ex coeff(const ex & s, int n = 1) const;
83 ex eval(int level = 0) const;
84 ex series(const relational & s, int order, unsigned options = 0) const;
85 ex normal(lst &sym_lst, lst &repl_lst, int level = 0) const;
86 ex to_rational(lst &repl_lst) const;
88 ex derivative(const symbol & s) const;
89 int compare_same_type(const basic & other) const;
90 bool is_equal_same_type(const basic & other) const;
91 unsigned return_type(void) const;
92 unsigned return_type_tinfo(void) const;
93 unsigned calchash(void) const;
95 // non-virtual functions in this class
97 void assign(const ex & value);
99 void set_name(const std::string & n) { name = n; }
100 std::string get_name(void) const { return name; }
102 std::string & autoname_prefix(void);
103 std::string default_TeX_name(void) const;
108 assigned_ex_info * asexinfop; ///< ptr to assigned expression, deprecated
109 unsigned serial; ///< unique serial number for comparison
110 std::string name; ///< printname of this symbol
111 std::string TeX_name; ///< LaTeX name of this symbol
113 static unsigned next_serial;
119 /** Return the symbol object handled by an ex. Deprecated: use ex_to<symbol>().
120 * This is unsafe: you need to check the type first. */
121 inline const symbol &ex_to_symbol(const ex &e)
123 return static_cast<const symbol &>(*e.bp);
126 /** Specialization of is_exactly_a<symbol>(obj) for symbol objects. */
127 template<> inline bool is_exactly_a<symbol>(const basic & obj)
129 return obj.tinfo()==TINFO_symbol;
132 // wrapper functions around member functions
133 inline void unassign(symbol & symarg)
134 { symarg.unassign(); }
136 inline int degree(const symbol & a, const ex & s)
137 { return a.degree(s); }
139 inline int ldegree(const symbol & a, const ex & s)
140 { return a.ldegree(s); }
144 #endif // ndef __GINAC_SYMBOL_H__