3 * Implementation of 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
36 GINAC_IMPLEMENT_REGISTERED_CLASS_NO_CTORS(symbol, basic)
39 // default ctor, dtor, copy ctor assignment operator and helpers
42 symbol::symbol() : inherited(TINFO_symbol), serial(next_serial++)
44 debugmsg("symbol default ctor", LOGLEVEL_CONSTRUCT);
45 name = TeX_name = autoname_prefix()+ToString(serial);
46 asexinfop = new assigned_ex_info;
47 setflag(status_flags::evaluated | status_flags::expanded);
50 /** For use by copy ctor and assignment operator. */
51 void symbol::copy(const symbol & other)
53 inherited::copy(other);
55 TeX_name = other.TeX_name;
56 serial = other.serial;
57 asexinfop = other.asexinfop;
58 ++asexinfop->refcount;
61 void symbol::destroy(bool call_parent)
63 if (--asexinfop->refcount == 0)
66 inherited::destroy(call_parent);
75 symbol::symbol(const symbol & other)
77 debugmsg("symbol copy ctor", LOGLEVEL_CONSTRUCT);
81 symbol::symbol(const std::string & initname) : inherited(TINFO_symbol)
83 debugmsg("symbol ctor from string", LOGLEVEL_CONSTRUCT);
85 TeX_name = default_TeX_name();
86 serial = next_serial++;
87 asexinfop = new assigned_ex_info;
88 setflag(status_flags::evaluated | status_flags::expanded);
91 symbol::symbol(const std::string & initname, const std::string & texname) : inherited(TINFO_symbol)
93 debugmsg("symbol ctor from string", LOGLEVEL_CONSTRUCT);
96 serial = next_serial++;
97 asexinfop = new assigned_ex_info;
98 setflag(status_flags::evaluated | status_flags::expanded);
105 /** Construct object from archive_node. */
106 symbol::symbol(const archive_node &n, const lst &sym_lst) : inherited(n, sym_lst)
108 debugmsg("symbol ctor from archive_node", LOGLEVEL_CONSTRUCT);
109 serial = next_serial++;
110 if (!(n.find_string("name", name)))
111 name = autoname_prefix() + ToString(serial);
112 if (!(n.find_string("TeXname", TeX_name)))
113 TeX_name = default_TeX_name();
114 asexinfop = new assigned_ex_info;
115 setflag(status_flags::evaluated);
118 /** Unarchive the object. */
119 ex symbol::unarchive(const archive_node &n, const lst &sym_lst)
121 ex s = (new symbol(n, sym_lst))->setflag(status_flags::dynallocated);
123 // If symbol is in sym_lst, return the existing symbol
124 for (unsigned i=0; i<sym_lst.nops(); i++) {
125 if (is_ex_of_type(sym_lst.op(i), symbol) && (ex_to<symbol>(sym_lst.op(i)).name == ex_to<symbol>(s).name))
126 return sym_lst.op(i);
131 /** Archive the object. */
132 void symbol::archive(archive_node &n) const
134 inherited::archive(n);
135 n.add_string("name", name);
136 if (TeX_name != default_TeX_name())
137 n.add_string("TeX_name", TeX_name);
141 // functions overriding virtual functions from base classes
146 basic *symbol::duplicate() const
148 debugmsg("symbol duplicate", LOGLEVEL_DUPLICATE);
149 return new symbol(*this);
152 void symbol::print(const print_context & c, unsigned level) const
154 debugmsg("symbol print", LOGLEVEL_PRINT);
156 if (is_of_type(c, print_tree)) {
158 c.s << std::string(level, ' ') << name << " (" << class_name() << ")"
159 << ", serial=" << serial
160 << std::hex << ", hash=0x" << hashvalue << ", flags=0x" << flags << std::dec
163 } else if (is_of_type(c, print_latex))
169 bool symbol::info(unsigned inf) const
171 if (inf==info_flags::symbol) return true;
172 if (inf==info_flags::polynomial ||
173 inf==info_flags::integer_polynomial ||
174 inf==info_flags::cinteger_polynomial ||
175 inf==info_flags::rational_polynomial ||
176 inf==info_flags::crational_polynomial ||
177 inf==info_flags::rational_function)
180 return inherited::info(inf);
183 int symbol::degree(const ex & s) const
185 return is_equal(*s.bp) ? 1 : 0;
188 int symbol::ldegree(const ex & s) const
190 return is_equal(*s.bp) ? 1 : 0;
193 ex symbol::coeff(const ex & s, int n) const
196 return n==1 ? _ex1() : _ex0();
198 return n==0 ? *this : _ex0();
201 ex symbol::eval(int level) const
203 if (level == -max_recursion_level)
204 throw(std::runtime_error("max recursion level reached"));
206 if (asexinfop->is_assigned) {
207 setflag(status_flags::evaluated);
209 return (asexinfop->assigned_expression);
211 return (asexinfop->assigned_expression).eval(level);
219 /** Implementation of ex::diff() for single differentiation of a symbol.
223 ex symbol::derivative(const symbol & s) const
225 if (compare_same_type(s))
231 int symbol::compare_same_type(const basic & other) const
233 GINAC_ASSERT(is_of_type(other,symbol));
234 const symbol *o = static_cast<const symbol *>(&other);
235 if (serial==o->serial) return 0;
236 return serial < o->serial ? -1 : 1;
239 bool symbol::is_equal_same_type(const basic & other) const
241 GINAC_ASSERT(is_of_type(other,symbol));
242 const symbol *o = static_cast<const symbol *>(&other);
243 return serial==o->serial;
246 unsigned symbol::calchash(void) const
248 // this is where the schoolbook method
249 // (golden_ratio_hash(tinfo()) ^ serial)
250 // is not good enough yet...
251 hashvalue = golden_ratio_hash(golden_ratio_hash(tinfo()) ^ serial);
252 setflag(status_flags::hash_calculated);
257 // virtual functions which can be overridden by derived classes
263 // non-virtual functions in this class
268 void symbol::assign(const ex & value)
270 asexinfop->is_assigned = 1;
271 asexinfop->assigned_expression = value;
272 clearflag(status_flags::evaluated | status_flags::expanded);
275 void symbol::unassign(void)
277 if (asexinfop->is_assigned) {
278 asexinfop->is_assigned = 0;
279 asexinfop->assigned_expression = _ex0();
281 setflag(status_flags::evaluated | status_flags::expanded);
286 /** Symbols not constructed with a string get one assigned using this
287 * prefix and a number. */
288 std::string & symbol::autoname_prefix(void)
290 static std::string *s = new std::string("symbol");
294 /** Return default TeX name for symbol. This recognizes some greek letters. */
295 std::string symbol::default_TeX_name(void) const
297 if (name=="alpha" || name=="beta" || name=="gamma"
298 || name=="delta" || name=="epsilon" || name=="varepsilon"
299 || name=="zeta" || name=="eta" || name=="theta"
300 || name=="vartheta" || name=="iota" || name=="kappa"
301 || name=="lambda" || name=="mu" || name=="nu"
302 || name=="xi" || name=="omicron" || name=="pi"
303 || name=="varpi" || name=="rho" || name=="varrho"
304 || name=="sigma" || name=="varsigma" || name=="tau"
305 || name=="upsilon" || name=="phi" || name=="varphi"
306 || name=="chi" || name=="psi" || name=="omega"
307 || name=="Gamma" || name=="Delta" || name=="Theta"
308 || name=="Lambda" || name=="Xi" || name=="Pi"
309 || name=="Sigma" || name=="Upsilon" || name=="Phi"
310 || name=="Psi" || name=="Omega")
317 // static member variables
322 unsigned symbol::next_serial = 0;
325 // subclass assigned_ex_info
328 /** Default ctor. Defaults to unassigned. */
329 symbol::assigned_ex_info::assigned_ex_info(void) : is_assigned(0), refcount(1)