ginac/add.cpp

   1 /** @file add.cpp
   2  *
   3  *  Implementation of GiNaC's sums of expressions. */
   4
   5 /*
   6  *  GiNaC Copyright (C) 1999-2000 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  21  */
  22
  23 #include <iostream>
  24 #include <stdexcept>
  25
  26 #include "add.h"
  27 #include "mul.h"
  28 #include "archive.h"
  29 #include "debugmsg.h"
  30 #include "utils.h"
  31
  32 #ifndef NO_NAMESPACE_GINAC
  33 namespace GiNaC {
  34 #endif // ndef NO_NAMESPACE_GINAC
  35
  36 GINAC_IMPLEMENT_REGISTERED_CLASS(add, expairseq)
  37
  38 //////////
  39 // default constructor, destructor, copy constructor assignment operator and helpers
  40 //////////
  41
  42 // public
  43
  44 add::add()
  45 {
  46         debugmsg("add default constructor",LOGLEVEL_CONSTRUCT);
  47         tinfo_key = TINFO_add;
  48 }
  49
  50 add::~add()
  51 {
  52         debugmsg("add destructor",LOGLEVEL_DESTRUCT);
  53         destroy(false);
  54 }
  55
  56 add::add(const add & other)
  57 {
  58         debugmsg("add copy constructor",LOGLEVEL_CONSTRUCT);
  59         copy(other);
  60 }
  61
  62 const add & add::operator=(const add & other)
  63 {
  64         debugmsg("add operator=",LOGLEVEL_ASSIGNMENT);
  65         if (this != &other) {
  66                 destroy(true);
  67                 copy(other);
  68         }
  69         return *this;
  70 }
  71
  72 // protected
  73
  74 void add::copy(const add & other)
  75 {
  76         inherited::copy(other);
  77 }
  78
  79 void add::destroy(bool call_parent)
  80 {
  81         if (call_parent) inherited::destroy(call_parent);
  82 }
  83
  84 //////////
  85 // other constructors
  86 //////////
  87
  88 // public
  89
  90 add::add(const ex & lh, const ex & rh)
  91 {
  92         debugmsg("add constructor from ex,ex",LOGLEVEL_CONSTRUCT);
  93         tinfo_key = TINFO_add;
  94         overall_coeff = _ex0();
  95         construct_from_2_ex(lh,rh);
  96         GINAC_ASSERT(is_canonical());
  97 }
  98
  99 add::add(const exvector & v)
 100 {
 101         debugmsg("add constructor from exvector",LOGLEVEL_CONSTRUCT);
 102         tinfo_key = TINFO_add;
 103         overall_coeff = _ex0();
 104         construct_from_exvector(v);
 105         GINAC_ASSERT(is_canonical());
 106 }
 107
 108 /*
 109 add::add(const epvector & v, bool do_not_canonicalize)
 110 {
 111         debugmsg("add constructor from epvector,bool",LOGLEVEL_CONSTRUCT);
 112         tinfo_key = TINFO_add;
 113         if (do_not_canonicalize) {
 114                 seq=v;
 115 #ifdef EXPAIRSEQ_USE_HASHTAB
 116                 combine_same_terms(); // to build hashtab
 117 #endif // def EXPAIRSEQ_USE_HASHTAB
 118         } else {
 119                 construct_from_epvector(v);
 120         }
 121         GINAC_ASSERT(is_canonical());
 122 }
 123 */
 124
 125 add::add(const epvector & v)
 126 {
 127         debugmsg("add constructor from epvector",LOGLEVEL_CONSTRUCT);
 128         tinfo_key = TINFO_add;
 129         overall_coeff = _ex0();
 130         construct_from_epvector(v);
 131         GINAC_ASSERT(is_canonical());
 132 }
 133
 134 add::add(const epvector & v, const ex & oc)
 135 {
 136         debugmsg("add constructor from epvector,ex",LOGLEVEL_CONSTRUCT);
 137         tinfo_key = TINFO_add;
 138         overall_coeff = oc;
 139         construct_from_epvector(v);
 140         GINAC_ASSERT(is_canonical());
 141 }
 142
 143 add::add(epvector * vp, const ex & oc)
 144 {
 145         debugmsg("add constructor from epvector *,ex",LOGLEVEL_CONSTRUCT);
 146         tinfo_key = TINFO_add;
 147         GINAC_ASSERT(vp!=0);
 148         overall_coeff = oc;
 149         construct_from_epvector(*vp);
 150         delete vp;
 151         GINAC_ASSERT(is_canonical());
 152 }
 153
 154 //////////
 155 // archiving
 156 //////////
 157
 158 /** Construct object from archive_node. */
 159 add::add(const archive_node &n, const lst &sym_lst) : inherited(n, sym_lst)
 160 {
 161         debugmsg("add constructor from archive_node", LOGLEVEL_CONSTRUCT);
 162 }
 163
 164 /** Unarchive the object. */
 165 ex add::unarchive(const archive_node &n, const lst &sym_lst)
 166 {
 167         return (new add(n, sym_lst))->setflag(status_flags::dynallocated);
 168 }
 169
 170 /** Archive the object. */
 171 void add::archive(archive_node &n) const
 172 {
 173         inherited::archive(n);
 174 }
 175
 176 //////////
 177 // functions overriding virtual functions from bases classes
 178 //////////
 179
 180 // public
 181
 182 basic * add::duplicate() const
 183 {
 184         debugmsg("add duplicate",LOGLEVEL_DUPLICATE);
 185         return new add(*this);
 186 }
 187
 188 void add::print(std::ostream & os, unsigned upper_precedence) const
 189 {
 190         debugmsg("add print",LOGLEVEL_PRINT);
 191         if (precedence<=upper_precedence) os << "(";
 192         numeric coeff;
 193         bool first = true;
 194         // first print the overall numeric coefficient, if present:
 195         if (!overall_coeff.is_zero()) {
 196                 os << overall_coeff;
 197                 first = false;
 198         }
 199         // then proceed with the remaining factors:
 200         for (epvector::const_iterator cit=seq.begin(); cit!=seq.end(); ++cit) {
 201                 coeff = ex_to_numeric(cit->coeff);
 202                 if (!first) {
 203                         if (coeff.csgn()==-1) os << '-'; else os << '+';
 204                 } else {
 205                         if (coeff.csgn()==-1) os << '-';
 206                         first = false;
 207                 }
 208                 if (!coeff.is_equal(_num1()) &&
 209                     !coeff.is_equal(_num_1())) {
 210                         if (coeff.is_rational()) {
 211                                 if (coeff.is_negative())
 212                                         os << -coeff;
 213                                 else
 214                                         os << coeff;
 215                         } else {
 216                                 if (coeff.csgn()==-1)
 217                                         (-coeff).print(os, precedence);
 218                                 else
 219                                         coeff.print(os, precedence);
 220                         }
 221                         os << '*';
 222                 }
 223                 cit->rest.print(os, precedence);
 224         }
 225         if (precedence<=upper_precedence) os << ")";
 226 }
 227
 228 void add::printraw(std::ostream & os) const
 229 {
 230         debugmsg("add printraw",LOGLEVEL_PRINT);
 231
 232         os << "+(";
 233         for (epvector::const_iterator it=seq.begin(); it!=seq.end(); ++it) {
 234                 os << "(";
 235                 (*it).rest.bp->printraw(os);
 236                 os << ",";
 237                 (*it).coeff.bp->printraw(os);
 238                 os << "),";
 239         }
 240         os << ",hash=" << hashvalue << ",flags=" << flags;
 241         os << ")";
 242 }
 243
 244 void add::printcsrc(std::ostream & os, unsigned type, unsigned upper_precedence) const
 245 {
 246         debugmsg("add print csrc", LOGLEVEL_PRINT);
 247         if (precedence <= upper_precedence)
 248                 os << "(";
 249
 250         // Print arguments, separated by "+"
 251         epvector::const_iterator it = seq.begin();
 252         epvector::const_iterator itend = seq.end();
 253         while (it != itend) {
 254
 255                 // If the coefficient is -1, it is replaced by a single minus sign
 256                 if (it->coeff.compare(_num1()) == 0) {
 257                         it->rest.bp->printcsrc(os, type, precedence);
 258                 } else if (it->coeff.compare(_num_1()) == 0) {
 259                         os << "-";
 260                         it->rest.bp->printcsrc(os, type, precedence);
 261                 } else if (ex_to_numeric(it->coeff).numer().compare(_num1()) == 0) {
 262                         it->rest.bp->printcsrc(os, type, precedence);
 263                         os << "/";
 264                         ex_to_numeric(it->coeff).denom().printcsrc(os, type, precedence);
 265                 } else if (ex_to_numeric(it->coeff).numer().compare(_num_1()) == 0) {
 266                         os << "-";
 267                         it->rest.bp->printcsrc(os, type, precedence);
 268                         os << "/";
 269                         ex_to_numeric(it->coeff).denom().printcsrc(os, type, precedence);
 270                 } else {
 271                         it->coeff.bp->printcsrc(os, type, precedence);
 272                         os << "*";
 273                         it->rest.bp->printcsrc(os, type, precedence);
 274                 }
 275
 276                 // Separator is "+", except if the following expression would have a leading minus sign
 277                 it++;
 278                 if (it != itend && !(it->coeff.compare(_num0()) < 0 || (it->coeff.compare(_num1()) == 0 && is_ex_exactly_of_type(it->rest, numeric) && it->rest.compare(_num0()) < 0)))
 279                         os << "+";
 280         }
 281
 282         if (!overall_coeff.is_equal(_ex0())) {
 283                 if (overall_coeff.info(info_flags::positive)) os << '+';
 284                 overall_coeff.bp->printcsrc(os,type,precedence);
 285         }
 286
 287         if (precedence <= upper_precedence)
 288                 os << ")";
 289 }
 290
 291 bool add::info(unsigned inf) const
 292 {
 293         switch (inf) {
 294                 case info_flags::polynomial:
 295                 case info_flags::integer_polynomial:
 296                 case info_flags::cinteger_polynomial:
 297                 case info_flags::rational_polynomial:
 298                 case info_flags::crational_polynomial:
 299                 case info_flags::rational_function: {
 300                         for (epvector::const_iterator i=seq.begin(); i!=seq.end(); ++i) {
 301                                 if (!(recombine_pair_to_ex(*i).info(inf)))
 302                                         return false;
 303                         }
 304                         return overall_coeff.info(inf);
 305                 }
 306                 case info_flags::algebraic: {
 307                         for (epvector::const_iterator i=seq.begin(); i!=seq.end(); ++i) {
 308                                 if ((recombine_pair_to_ex(*i).info(inf)))
 309                                         return true;
 310                         }
 311                         return false;
 312                 }
 313         }
 314         return inherited::info(inf);
 315 }
 316
 317 int add::degree(const symbol & s) const
 318 {
 319         int deg = INT_MIN;
 320         if (!overall_coeff.is_equal(_ex0())) {
 321                 deg = 0;
 322         }
 323         int cur_deg;
 324         for (epvector::const_iterator cit=seq.begin(); cit!=seq.end(); ++cit) {
 325                 cur_deg=(*cit).rest.degree(s);
 326                 if (cur_deg>deg) deg=cur_deg;
 327         }
 328         return deg;
 329 }
 330
 331 int add::ldegree(const symbol & s) const
 332 {
 333         int deg = INT_MAX;
 334         if (!overall_coeff.is_equal(_ex0())) {
 335                 deg = 0;
 336         }
 337         int cur_deg;
 338         for (epvector::const_iterator cit=seq.begin(); cit!=seq.end(); ++cit) {
 339                 cur_deg = (*cit).rest.ldegree(s);
 340                 if (cur_deg<deg) deg=cur_deg;
 341         }
 342         return deg;
 343 }
 344
 345 ex add::coeff(const symbol & s, int n) const
 346 {
 347         epvector coeffseq;
 348         coeffseq.reserve(seq.size());
 349
 350         epvector::const_iterator it=seq.begin();
 351         while (it!=seq.end()) {
 352                 coeffseq.push_back(combine_ex_with_coeff_to_pair((*it).rest.coeff(s,n),
 353                                                                  (*it).coeff));
 354                 ++it;
 355         }
 356         if (n==0) {
 357                 return (new add(coeffseq,overall_coeff))->setflag(status_flags::dynallocated);
 358         }
 359         return (new add(coeffseq))->setflag(status_flags::dynallocated);
 360 }
 361
 362 ex add::eval(int level) const
 363 {
 364         // simplifications: +(;c) -> c
 365         //                  +(x;1) -> x
 366
 367         debugmsg("add eval",LOGLEVEL_MEMBER_FUNCTION);
 368
 369         epvector * evaled_seqp=evalchildren(level);
 370         if (evaled_seqp!=0) {
 371                 // do more evaluation later
 372                 return (new add(evaled_seqp,overall_coeff))->
 373                        setflag(status_flags::dynallocated);
 374         }
 375
 376 #ifdef DO_GINAC_ASSERT
 377         for (epvector::const_iterator cit=seq.begin(); cit!=seq.end(); ++cit) {
 378                 GINAC_ASSERT(!is_ex_exactly_of_type((*cit).rest,add));
 379                 if (is_ex_exactly_of_type((*cit).rest,numeric)) {
 380                         dbgprint();
 381                 }
 382                 GINAC_ASSERT(!is_ex_exactly_of_type((*cit).rest,numeric));
 383         }
 384 #endif // def DO_GINAC_ASSERT
 385
 386         if (flags & status_flags::evaluated) {
 387                 GINAC_ASSERT(seq.size()>0);
 388                 GINAC_ASSERT((seq.size()>1)||!overall_coeff.is_equal(_ex0()));
 389                 return *this;
 390         }
 391
 392         int seq_size=seq.size();
 393         if (seq_size==0) {
 394                 // +(;c) -> c
 395                 return overall_coeff;
 396         } else if ((seq_size==1)&&overall_coeff.is_equal(_ex0())) {
 397                 // +(x;0) -> x
 398                 return recombine_pair_to_ex(*(seq.begin()));
 399         }
 400         return this->hold();
 401 }
 402
 403 exvector add::get_indices(void) const
 404 {
 405         // FIXME: all terms in the sum should have the same indices (compatible
 406         // tensors) however this is not checked, since there is no function yet
 407         // which compares indices (idxvector can be unsorted)
 408         if (seq.size()==0) {
 409                 return exvector();
 410         }
 411         return (seq.begin())->rest.get_indices();
 412 }
 413
 414 ex add::simplify_ncmul(const exvector & v) const
 415 {
 416         if (seq.size()==0) {
 417                 return inherited::simplify_ncmul(v);
 418         }
 419         return (*seq.begin()).rest.simplify_ncmul(v);
 420 }
 421
 422 // protected
 423
 424 /** Implementation of ex::diff() for a sum. It differentiates each term.
 425  *  @see ex::diff */
 426 ex add::derivative(const symbol & s) const
 427 {
 428         // D(a+b+c)=D(a)+D(b)+D(c)
 429         return (new add(diffchildren(s)))->setflag(status_flags::dynallocated);
 430 }
 431
 432 int add::compare_same_type(const basic & other) const
 433 {
 434         return inherited::compare_same_type(other);
 435 }
 436
 437 bool add::is_equal_same_type(const basic & other) const
 438 {
 439         return inherited::is_equal_same_type(other);
 440 }
 441
 442 unsigned add::return_type(void) const
 443 {
 444         if (seq.size()==0) {
 445                 return return_types::commutative;
 446         }
 447         return (*seq.begin()).rest.return_type();
 448 }
 449
 450 unsigned add::return_type_tinfo(void) const
 451 {
 452         if (seq.size()==0) {
 453                 return tinfo_key;
 454         }
 455         return (*seq.begin()).rest.return_type_tinfo();
 456 }
 457
 458 ex add::thisexpairseq(const epvector & v, const ex & oc) const
 459 {
 460         return (new add(v,oc))->setflag(status_flags::dynallocated);
 461 }
 462
 463 ex add::thisexpairseq(epvector * vp, const ex & oc) const
 464 {
 465         return (new add(vp,oc))->setflag(status_flags::dynallocated);
 466 }
 467
 468 expair add::split_ex_to_pair(const ex & e) const
 469 {
 470         if (is_ex_exactly_of_type(e,mul)) {
 471                 const mul & mulref=ex_to_mul(e);
 472                 ex numfactor=mulref.overall_coeff;
 473                 // mul * mulcopyp=static_cast<mul *>(mulref.duplicate());
 474                 mul * mulcopyp=new mul(mulref);
 475                 mulcopyp->overall_coeff=_ex1();
 476                 mulcopyp->clearflag(status_flags::evaluated);
 477                 mulcopyp->clearflag(status_flags::hash_calculated);
 478                 return expair(mulcopyp->setflag(status_flags::dynallocated),numfactor);
 479         }
 480         return expair(e,_ex1());
 481 }
 482
 483 expair add::combine_ex_with_coeff_to_pair(const ex & e,
 484                                                                                   const ex & c) const
 485 {
 486         GINAC_ASSERT(is_ex_exactly_of_type(c, numeric));
 487         ex one = _ex1();
 488         if (is_ex_exactly_of_type(e, mul)) {
 489                 const mul &mulref = ex_to_mul(e);
 490                 ex numfactor = mulref.overall_coeff;
 491                 mul *mulcopyp = new mul(mulref);
 492                 mulcopyp->overall_coeff = one;
 493                 mulcopyp->clearflag(status_flags::evaluated);
 494                 mulcopyp->clearflag(status_flags::hash_calculated);
 495                 mulcopyp->setflag(status_flags::dynallocated);
 496                 if (are_ex_trivially_equal(c, one)) {
 497                         return expair(*mulcopyp, numfactor);
 498                 } else if (are_ex_trivially_equal(numfactor, one)) {
 499                         return expair(*mulcopyp, c);
 500                 }
 501                 return expair(*mulcopyp, ex_to_numeric(numfactor).mul_dyn(ex_to_numeric(c)));
 502         } else if (is_ex_exactly_of_type(e, numeric)) {
 503                 if (are_ex_trivially_equal(c, one)) {
 504                         return expair(e, one);
 505                 }
 506                 return expair(ex_to_numeric(e).mul_dyn(ex_to_numeric(c)), one);
 507         }
 508         return expair(e, c);
 509 }
 510
 511 expair add::combine_pair_with_coeff_to_pair(const expair & p,
 512                                                                                         const ex & c) const
 513 {
 514         GINAC_ASSERT(is_ex_exactly_of_type(p.coeff,numeric));
 515         GINAC_ASSERT(is_ex_exactly_of_type(c,numeric));
 516
 517         if (is_ex_exactly_of_type(p.rest,numeric)) {
 518                 GINAC_ASSERT(ex_to_numeric(p.coeff).is_equal(_num1())); // should be normalized
 519                 return expair(ex_to_numeric(p.rest).mul_dyn(ex_to_numeric(c)),_ex1());
 520         }
 521
 522         return expair(p.rest,ex_to_numeric(p.coeff).mul_dyn(ex_to_numeric(c)));
 523 }
 524
 525 ex add::recombine_pair_to_ex(const expair & p) const
 526 {
 527         if (ex_to_numeric(p.coeff).is_equal(_num1()))
 528                 return p.rest;
 529         else
 530                 return p.rest*p.coeff;
 531 }
 532
 533 ex add::expand(unsigned options) const
 534 {
 535         if (flags & status_flags::expanded)
 536                 return *this;
 537
 538         epvector * vp = expandchildren(options);
 539         if (vp==0)
 540                 return *this;
 541
 542         return (new add(vp,overall_coeff))->setflag(status_flags::expanded | status_flags::dynallocated);
 543 }
 544
 545 //////////
 546 // new virtual functions which can be overridden by derived classes
 547 //////////
 548
 549 // none
 550
 551 //////////
 552 // non-virtual functions in this class
 553 //////////
 554
 555 // none
 556
 557 //////////
 558 // static member variables
 559 //////////
 560
 561 // protected
 562
 563 unsigned add::precedence = 40;
 564
 565 //////////
 566 // global constants
 567 //////////
 568
 569 const add some_add;
 570 const std::type_info & typeid_add = typeid(some_add);
 571
 572 #ifndef NO_NAMESPACE_GINAC
 573 } // namespace GiNaC
 574 #endif // ndef NO_NAMESPACE_GINAC