ginac/symbol.cpp

   1 /** @file symbol.cpp
   2  *
   3  *  Implementation of GiNaC's symbolic objects. */
   4
   5 /*
   6  *  GiNaC Copyright (C) 1999-2008 Johannes Gutenberg University Mainz, Germany
   7  *
   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.
  12  *
  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.
  17  *
  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., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
  21  */
  22
  23 #include <string>
  24 #include <stdexcept>
  25 #include <map>
  26
  27 #include "symbol.h"
  28 #include "lst.h"
  29 #include "archive.h"
  30 #include "tostring.h"
  31 #include "utils.h"
  32 #include "inifcns.h"
  33
  34 namespace GiNaC {
  35
  36 GINAC_IMPLEMENT_REGISTERED_CLASS_OPT(symbol, basic,
  37   print_func<print_context>(&symbol::do_print).
  38   print_func<print_latex>(&symbol::do_print_latex).
  39   print_func<print_tree>(&symbol::do_print_tree).
  40   print_func<print_python_repr>(&symbol::do_print_python_repr))
  41
  42 //////////
  43 // default constructor
  44 //////////
  45
  46 // symbol
  47
  48 symbol::symbol() : serial(next_serial++), name(""), TeX_name("")
  49 {
  50         setflag(status_flags::evaluated | status_flags::expanded);
  51 }
  52
  53 // realsymbol
  54
  55 realsymbol::realsymbol() : symbol() { }
  56
  57 // possymbol
  58
  59 possymbol::possymbol() : realsymbol() { }
  60
  61 //////////
  62 // other constructors
  63 //////////
  64
  65 // public
  66
  67 // symbol
  68
  69 symbol::symbol(const std::string & initname) : serial(next_serial++),
  70         name(initname), TeX_name("")
  71 {
  72         setflag(status_flags::evaluated | status_flags::expanded);
  73 }
  74
  75 symbol::symbol(const std::string & initname, const std::string & texname) :
  76         serial(next_serial++), name(initname), TeX_name(texname)
  77 {
  78         setflag(status_flags::evaluated | status_flags::expanded);
  79 }
  80
  81 // realsymbol
  82
  83 realsymbol::realsymbol(const std::string & initname) : symbol(initname) { }
  84
  85 realsymbol::realsymbol(const std::string & initname, const std::string & texname)
  86         : symbol(initname, texname) { }
  87
  88 // possymbol
  89
  90 possymbol::possymbol(const std::string & initname) : realsymbol(initname) { }
  91
  92 possymbol::possymbol(const std::string & initname, const std::string & texname)
  93         : realsymbol(initname, texname) { }
  94
  95 //////////
  96 // archiving
  97 //////////
  98
  99 /** Construct object from archive_node. */
 100 symbol::symbol(const archive_node &n, lst &sym_lst)
 101  : inherited(n, sym_lst), serial(next_serial++)
 102 {
 103         if (!n.find_string("name", name))
 104                 name = std::string("");
 105         if (!n.find_string("TeXname", TeX_name))
 106                 TeX_name = std::string("");
 107         setflag(status_flags::evaluated | status_flags::expanded);
 108 }
 109
 110 /** Unarchive the object. */
 111 ex symbol::unarchive(const archive_node &n, lst &sym_lst)
 112 {
 113         ex s = (new symbol(n, sym_lst))->setflag(status_flags::dynallocated);
 114
 115         // If symbol is in sym_lst, return the existing symbol
 116         for (lst::const_iterator it = sym_lst.begin(); it != sym_lst.end(); ++it) {
 117                 if (is_a<symbol>(*it) && (ex_to<symbol>(*it).name == ex_to<symbol>(s).name))
 118                         return *it;
 119         }
 120
 121         // Otherwise add new symbol to list and return it
 122         sym_lst.append(s);
 123         return s;
 124 }
 125
 126 /** Archive the object. */
 127 void symbol::archive(archive_node &n) const
 128 {
 129         inherited::archive(n);
 130         // XXX: we should not archive anonymous symbols.
 131         if (!name.empty())
 132                 n.add_string("name", name);
 133         if (!TeX_name.empty())
 134                 n.add_string("TeX_name", TeX_name);
 135 }
 136
 137 //////////
 138 // functions overriding virtual functions from base classes
 139 //////////
 140
 141 /** Return default TeX name for symbol. This recognizes some greek letters. */
 142 static const std::string& get_default_TeX_name(const std::string& name);
 143
 144 // public
 145
 146 void symbol::do_print(const print_context & c, unsigned level) const
 147 {
 148         if (!name.empty())
 149                 c.s << name;
 150         else
 151                 c.s << "symbol" << serial;
 152 }
 153
 154 void symbol::do_print_latex(const print_latex & c, unsigned level) const
 155 {
 156         if (!TeX_name.empty())
 157                 c.s << TeX_name;
 158         else if (!name.empty())
 159                 c.s << get_default_TeX_name(name);
 160         else
 161                 c.s << "symbol" << serial;
 162 }
 163
 164 void symbol::do_print_tree(const print_tree & c, unsigned level) const
 165 {
 166         c.s << std::string(level, ' ') << name << " (" << class_name() << ")" << " @" << this
 167             << ", serial=" << serial
 168             << std::hex << ", hash=0x" << hashvalue << ", flags=0x" << flags << std::dec
 169             << ", domain=" << get_domain()
 170             << std::endl;
 171 }
 172
 173 void symbol::do_print_python_repr(const print_python_repr & c, unsigned level) const
 174 {
 175         c.s << class_name() << "('";
 176         if (!name.empty())
 177                 c.s << name;
 178         else
 179                 c.s << "symbol" << serial;
 180         if (!TeX_name.empty())
 181                 c.s << "','" << TeX_name;
 182         c.s << "')";
 183 }
 184
 185 bool symbol::info(unsigned inf) const
 186 {
 187         switch (inf) {
 188                 case info_flags::symbol:
 189                 case info_flags::polynomial:
 190                 case info_flags::integer_polynomial:
 191                 case info_flags::cinteger_polynomial:
 192                 case info_flags::rational_polynomial:
 193                 case info_flags::crational_polynomial:
 194                 case info_flags::rational_function:
 195                 case info_flags::expanded:
 196                         return true;
 197                 case info_flags::real:
 198                         return get_domain() == domain::real || get_domain() == domain::positive;
 199                 case info_flags::positive:
 200                 case info_flags::nonnegative:
 201                         return get_domain() == domain::positive;
 202                 case info_flags::has_indices:
 203                         return false;
 204         }
 205         return inherited::info(inf);
 206 }
 207
 208 ex symbol::conjugate() const
 209 {
 210         return conjugate_function(*this).hold();
 211 }
 212
 213 ex symbol::real_part() const
 214 {
 215         return real_part_function(*this).hold();
 216 }
 217
 218 ex symbol::imag_part() const
 219 {
 220         return imag_part_function(*this).hold();
 221 }
 222
 223 bool symbol::is_polynomial(const ex & var) const
 224 {
 225         return true;
 226 }
 227
 228 // protected
 229
 230 /** Implementation of ex::diff() for single differentiation of a symbol.
 231  *  It returns 1 or 0.
 232  *
 233  *  @see ex::diff */
 234 ex symbol::derivative(const symbol & s) const
 235 {
 236         if (compare_same_type(s))
 237                 return _ex0;
 238         else
 239                 return _ex1;
 240 }
 241
 242 int symbol::compare_same_type(const basic & other) const
 243 {
 244         GINAC_ASSERT(is_a<symbol>(other));
 245         const symbol *o = static_cast<const symbol *>(&other);
 246         if (serial==o->serial) return 0;
 247         return serial < o->serial ? -1 : 1;
 248 }
 249
 250 bool symbol::is_equal_same_type(const basic & other) const
 251 {
 252         GINAC_ASSERT(is_a<symbol>(other));
 253         const symbol *o = static_cast<const symbol *>(&other);
 254         return serial==o->serial;
 255 }
 256
 257 unsigned symbol::calchash() const
 258 {
 259         const void* this_tinfo = (const void*)typeid(*this).name();
 260         hashvalue = golden_ratio_hash((p_int)this_tinfo ^ serial);
 261         setflag(status_flags::hash_calculated);
 262         return hashvalue;
 263 }
 264
 265 //////////
 266 // virtual functions which can be overridden by derived classes
 267 //////////
 268
 269 // none
 270
 271 //////////
 272 // non-virtual functions in this class
 273 //////////
 274
 275 /** Return default TeX name for symbol. This recognizes some greek letters. */
 276 static const std::string& get_default_TeX_name(const std::string& name)
 277 {
 278         static std::map<std::string, std::string> standard_names;
 279         static bool names_initialized = false;
 280         if (!names_initialized) {
 281                 standard_names["alpha"] = std::string("\\alpha");
 282                 standard_names["beta"] = std::string("\\beta");;
 283                 standard_names["gamma"] = std::string("\\gamma");;
 284                 standard_names["delta"] = std::string("\\delta");;
 285                 standard_names["epsilon"] = std::string("\\epsilon");
 286                 standard_names["varepsilon"] = std::string("\\varepsilon");
 287                 standard_names["zeta"] = std::string("\\zeta");
 288                 standard_names["eta" ] = std::string("\\eta" );
 289                 standard_names["theta"] = std::string("\\theta");
 290                 standard_names["vartheta"] = std::string("\\vartheta");
 291                 standard_names["iota"] = std::string("\\iota");
 292                 standard_names["kappa"] = std::string("\\kappa");
 293                 standard_names["lambda"] = std::string("\\lambda");
 294                 standard_names["mu"] = std::string("\\mu");
 295                 standard_names["nu"] = std::string("\\nu");
 296                 standard_names["xi"] = std::string("\\xi");
 297                 standard_names["omicron"] = std::string("\\omicron");
 298                 standard_names["pi"] = std::string("\\pi");
 299                 standard_names["varpi"] = std::string("\\varpi");
 300                 standard_names["rho"] = std::string("\\rho");
 301                 standard_names["varrho"] = std::string("\\varrho");
 302                 standard_names["sigma"] = std::string("\\sigma");
 303                 standard_names["varsigma"] = std::string("\\varsigma");
 304                 standard_names["tau"] = std::string("\\tau");
 305                 standard_names["upsilon"] = std::string("\\upsilon");
 306                 standard_names["phi"] = std::string("\\phi");
 307                 standard_names["varphi"] = std::string("\\varphi");
 308                 standard_names["chi"] = std::string("\\chi");
 309                 standard_names["psi"] = std::string("\\psi");
 310                 standard_names["omega"] = std::string("\\omega");
 311                 standard_names["Gamma"] = std::string("\\Gamma");
 312                 standard_names["Delta"] = std::string("\\Delta");
 313                 standard_names["Theta"] = std::string("\\Theta");
 314                 standard_names["Lambda"] = std::string("\\Lambda");
 315                 standard_names["Xi"] = std::string("\\Xi");
 316                 standard_names["Pi"] = std::string("\\Pi");
 317                 standard_names["Sigma"] = std::string("\\Sigma");
 318                 standard_names["Upsilon"] = std::string("\\Upsilon");
 319                 standard_names["Phi"] = std::string("\\Phi");
 320                 standard_names["Psi"] = std::string("\\Psi");
 321                 standard_names["Omega"] = std::string("\\Omega");
 322                 names_initialized = true;
 323         }
 324         std::map<std::string, std::string>::const_iterator it = standard_names.find(name);
 325         if (it != standard_names.end())
 326                 return it->second;
 327         else
 328                 return name;
 329 }
 330
 331 //////////
 332 // static member variables
 333 //////////
 334
 335 // private
 336
 337 unsigned symbol::next_serial = 0;
 338
 339 } // namespace GiNaC