ginac/add.cpp

   1 /** @file add.cpp
   2  *
   3  *  Implementation of GiNaC's sums of expressions. */
   4
   5 /*
   6  *  GiNaC Copyright (C) 1999-2001 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 // protected
  51
  52 void add::copy(const add & other)
  53 {
  54         inherited::copy(other);
  55 }
  56
  57 void add::destroy(bool call_parent)
  58 {
  59         if (call_parent) inherited::destroy(call_parent);
  60 }
  61
  62 //////////
  63 // other constructors
  64 //////////
  65
  66 // public
  67
  68 add::add(const ex & lh, const ex & rh)
  69 {
  70         debugmsg("add constructor from ex,ex",LOGLEVEL_CONSTRUCT);
  71         tinfo_key = TINFO_add;
  72         overall_coeff = _ex0();
  73         construct_from_2_ex(lh,rh);
  74         GINAC_ASSERT(is_canonical());
  75 }
  76
  77 add::add(const exvector & v)
  78 {
  79         debugmsg("add constructor from exvector",LOGLEVEL_CONSTRUCT);
  80         tinfo_key = TINFO_add;
  81         overall_coeff = _ex0();
  82         construct_from_exvector(v);
  83         GINAC_ASSERT(is_canonical());
  84 }
  85
  86 /*
  87 add::add(const epvector & v, bool do_not_canonicalize)
  88 {
  89         debugmsg("add constructor from epvector,bool",LOGLEVEL_CONSTRUCT);
  90         tinfo_key = TINFO_add;
  91         if (do_not_canonicalize) {
  92                 seq=v;
  93 #ifdef EXPAIRSEQ_USE_HASHTAB
  94                 combine_same_terms(); // to build hashtab
  95 #endif // def EXPAIRSEQ_USE_HASHTAB
  96         } else {
  97                 construct_from_epvector(v);
  98         }
  99         GINAC_ASSERT(is_canonical());
 100 }
 101 */
 102
 103 add::add(const epvector & v)
 104 {
 105         debugmsg("add constructor from epvector",LOGLEVEL_CONSTRUCT);
 106         tinfo_key = TINFO_add;
 107         overall_coeff = _ex0();
 108         construct_from_epvector(v);
 109         GINAC_ASSERT(is_canonical());
 110 }
 111
 112 add::add(const epvector & v, const ex & oc)
 113 {
 114         debugmsg("add constructor from epvector,ex",LOGLEVEL_CONSTRUCT);
 115         tinfo_key = TINFO_add;
 116         overall_coeff = oc;
 117         construct_from_epvector(v);
 118         GINAC_ASSERT(is_canonical());
 119 }
 120
 121 add::add(epvector * vp, const ex & oc)
 122 {
 123         debugmsg("add constructor from epvector *,ex",LOGLEVEL_CONSTRUCT);
 124         tinfo_key = TINFO_add;
 125         GINAC_ASSERT(vp!=0);
 126         overall_coeff = oc;
 127         construct_from_epvector(*vp);
 128         delete vp;
 129         GINAC_ASSERT(is_canonical());
 130 }
 131
 132 //////////
 133 // archiving
 134 //////////
 135
 136 /** Construct object from archive_node. */
 137 add::add(const archive_node &n, const lst &sym_lst) : inherited(n, sym_lst)
 138 {
 139         debugmsg("add constructor from archive_node", LOGLEVEL_CONSTRUCT);
 140 }
 141
 142 /** Unarchive the object. */
 143 ex add::unarchive(const archive_node &n, const lst &sym_lst)
 144 {
 145         return (new add(n, sym_lst))->setflag(status_flags::dynallocated);
 146 }
 147
 148 /** Archive the object. */
 149 void add::archive(archive_node &n) const
 150 {
 151         inherited::archive(n);
 152 }
 153
 154 //////////
 155 // functions overriding virtual functions from bases classes
 156 //////////
 157
 158 // public
 159
 160 void add::print(std::ostream & os, unsigned upper_precedence) const
 161 {
 162         debugmsg("add print",LOGLEVEL_PRINT);
 163         if (precedence<=upper_precedence) os << "(";
 164         numeric coeff;
 165         bool first = true;
 166         // first print the overall numeric coefficient, if present:
 167         if (!overall_coeff.is_zero()) {
 168                 os << overall_coeff;
 169                 first = false;
 170         }
 171         // then proceed with the remaining factors:
 172         for (epvector::const_iterator cit=seq.begin(); cit!=seq.end(); ++cit) {
 173                 coeff = ex_to_numeric(cit->coeff);
 174                 if (!first) {
 175                         if (coeff.csgn()==-1) os << '-'; else os << '+';
 176                 } else {
 177                         if (coeff.csgn()==-1) os << '-';
 178                         first = false;
 179                 }
 180                 if (!coeff.is_equal(_num1()) &&
 181                     !coeff.is_equal(_num_1())) {
 182                         if (coeff.is_rational()) {
 183                                 if (coeff.is_negative())
 184                                         os << -coeff;
 185                                 else
 186                                         os << coeff;
 187                         } else {
 188                                 if (coeff.csgn()==-1)
 189                                         (-coeff).print(os, precedence);
 190                                 else
 191                                         coeff.print(os, precedence);
 192                         }
 193                         os << '*';
 194                 }
 195                 cit->rest.print(os, precedence);
 196         }
 197         if (precedence<=upper_precedence) os << ")";
 198 }
 199
 200 void add::printraw(std::ostream & os) const
 201 {
 202         debugmsg("add printraw",LOGLEVEL_PRINT);
 203
 204         os << "+(";
 205         for (epvector::const_iterator it=seq.begin(); it!=seq.end(); ++it) {
 206                 os << "(";
 207                 (*it).rest.bp->printraw(os);
 208                 os << ",";
 209                 (*it).coeff.bp->printraw(os);
 210                 os << "),";
 211         }
 212         os << ",hash=" << hashvalue << ",flags=" << flags;
 213         os << ")";
 214 }
 215
 216 void add::printcsrc(std::ostream & os, unsigned type, unsigned upper_precedence) const
 217 {
 218         debugmsg("add print csrc", LOGLEVEL_PRINT);
 219         if (precedence <= upper_precedence)
 220                 os << "(";
 221
 222         // Print arguments, separated by "+"
 223         epvector::const_iterator it = seq.begin();
 224         epvector::const_iterator itend = seq.end();
 225         while (it != itend) {
 226
 227                 // If the coefficient is -1, it is replaced by a single minus sign
 228                 if (it->coeff.compare(_num1()) == 0) {
 229                         it->rest.bp->printcsrc(os, type, precedence);
 230                 } else if (it->coeff.compare(_num_1()) == 0) {
 231                         os << "-";
 232                         it->rest.bp->printcsrc(os, type, precedence);
 233                 } else if (ex_to_numeric(it->coeff).numer().compare(_num1()) == 0) {
 234                         it->rest.bp->printcsrc(os, type, precedence);
 235                         os << "/";
 236                         ex_to_numeric(it->coeff).denom().printcsrc(os, type, precedence);
 237                 } else if (ex_to_numeric(it->coeff).numer().compare(_num_1()) == 0) {
 238                         os << "-";
 239                         it->rest.bp->printcsrc(os, type, precedence);
 240                         os << "/";
 241                         ex_to_numeric(it->coeff).denom().printcsrc(os, type, precedence);
 242                 } else {
 243                         it->coeff.bp->printcsrc(os, type, precedence);
 244                         os << "*";
 245                         it->rest.bp->printcsrc(os, type, precedence);
 246                 }
 247
 248                 // Separator is "+", except if the following expression would have a leading minus sign
 249                 it++;
 250                 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)))
 251                         os << "+";
 252         }
 253
 254         if (!overall_coeff.is_equal(_ex0())) {
 255                 if (overall_coeff.info(info_flags::positive)) os << '+';
 256                 overall_coeff.bp->printcsrc(os,type,precedence);
 257         }
 258
 259         if (precedence <= upper_precedence)
 260                 os << ")";
 261 }
 262
 263 bool add::info(unsigned inf) const
 264 {
 265         switch (inf) {
 266                 case info_flags::polynomial:
 267                 case info_flags::integer_polynomial:
 268                 case info_flags::cinteger_polynomial:
 269                 case info_flags::rational_polynomial:
 270                 case info_flags::crational_polynomial:
 271                 case info_flags::rational_function: {
 272                         for (epvector::const_iterator i=seq.begin(); i!=seq.end(); ++i) {
 273                                 if (!(recombine_pair_to_ex(*i).info(inf)))
 274                                         return false;
 275                         }
 276                         return overall_coeff.info(inf);
 277                 }
 278                 case info_flags::algebraic: {
 279                         for (epvector::const_iterator i=seq.begin(); i!=seq.end(); ++i) {
 280                                 if ((recombine_pair_to_ex(*i).info(inf)))
 281                                         return true;
 282                         }
 283                         return false;
 284                 }
 285         }
 286         return inherited::info(inf);
 287 }
 288
 289 int add::degree(const symbol & s) const
 290 {
 291         int deg = INT_MIN;
 292         if (!overall_coeff.is_equal(_ex0())) {
 293                 deg = 0;
 294         }
 295         int cur_deg;
 296         for (epvector::const_iterator cit=seq.begin(); cit!=seq.end(); ++cit) {
 297                 cur_deg=(*cit).rest.degree(s);
 298                 if (cur_deg>deg) deg=cur_deg;
 299         }
 300         return deg;
 301 }
 302
 303 int add::ldegree(const symbol & s) const
 304 {
 305         int deg = INT_MAX;
 306         if (!overall_coeff.is_equal(_ex0())) {
 307                 deg = 0;
 308         }
 309         int cur_deg;
 310         for (epvector::const_iterator cit=seq.begin(); cit!=seq.end(); ++cit) {
 311                 cur_deg = (*cit).rest.ldegree(s);
 312                 if (cur_deg<deg) deg=cur_deg;
 313         }
 314         return deg;
 315 }
 316
 317 ex add::coeff(const symbol & s, int n) const
 318 {
 319         epvector coeffseq;
 320         coeffseq.reserve(seq.size());
 321
 322         epvector::const_iterator it=seq.begin();
 323         while (it!=seq.end()) {
 324                 coeffseq.push_back(combine_ex_with_coeff_to_pair((*it).rest.coeff(s,n),
 325                                                                  (*it).coeff));
 326                 ++it;
 327         }
 328         if (n==0) {
 329                 return (new add(coeffseq,overall_coeff))->setflag(status_flags::dynallocated);
 330         }
 331         return (new add(coeffseq))->setflag(status_flags::dynallocated);
 332 }
 333
 334 ex add::eval(int level) const
 335 {
 336         // simplifications: +(;c) -> c
 337         //                  +(x;1) -> x
 338
 339         debugmsg("add eval",LOGLEVEL_MEMBER_FUNCTION);
 340
 341         epvector * evaled_seqp=evalchildren(level);
 342         if (evaled_seqp!=0) {
 343                 // do more evaluation later
 344                 return (new add(evaled_seqp,overall_coeff))->
 345                        setflag(status_flags::dynallocated);
 346         }
 347
 348 #ifdef DO_GINAC_ASSERT
 349         for (epvector::const_iterator cit=seq.begin(); cit!=seq.end(); ++cit) {
 350                 GINAC_ASSERT(!is_ex_exactly_of_type((*cit).rest,add));
 351                 if (is_ex_exactly_of_type((*cit).rest,numeric)) {
 352                         dbgprint();
 353                 }
 354                 GINAC_ASSERT(!is_ex_exactly_of_type((*cit).rest,numeric));
 355         }
 356 #endif // def DO_GINAC_ASSERT
 357
 358         if (flags & status_flags::evaluated) {
 359                 GINAC_ASSERT(seq.size()>0);
 360                 GINAC_ASSERT((seq.size()>1)||!overall_coeff.is_equal(_ex0()));
 361                 return *this;
 362         }
 363
 364         int seq_size=seq.size();
 365         if (seq_size==0) {
 366                 // +(;c) -> c
 367                 return overall_coeff;
 368         } else if ((seq_size==1)&&overall_coeff.is_equal(_ex0())) {
 369                 // +(x;0) -> x
 370                 return recombine_pair_to_ex(*(seq.begin()));
 371         }
 372         return this->hold();
 373 }
 374
 375 exvector add::get_indices(void) const
 376 {
 377         // FIXME: all terms in the sum should have the same indices (compatible
 378         // tensors) however this is not checked, since there is no function yet
 379         // which compares indices (idxvector can be unsorted)
 380         if (seq.size()==0) {
 381                 return exvector();
 382         }
 383         return (seq.begin())->rest.get_indices();
 384 }
 385
 386 ex add::simplify_ncmul(const exvector & v) const
 387 {
 388         if (seq.size()==0) {
 389                 return inherited::simplify_ncmul(v);
 390         }
 391         return (*seq.begin()).rest.simplify_ncmul(v);
 392 }
 393
 394 // protected
 395
 396 /** Implementation of ex::diff() for a sum. It differentiates each term.
 397  *  @see ex::diff */
 398 ex add::derivative(const symbol & s) const
 399 {
 400         // D(a+b+c)=D(a)+D(b)+D(c)
 401         return (new add(diffchildren(s)))->setflag(status_flags::dynallocated);
 402 }
 403
 404 int add::compare_same_type(const basic & other) const
 405 {
 406         return inherited::compare_same_type(other);
 407 }
 408
 409 bool add::is_equal_same_type(const basic & other) const
 410 {
 411         return inherited::is_equal_same_type(other);
 412 }
 413
 414 unsigned add::return_type(void) const
 415 {
 416         if (seq.size()==0) {
 417                 return return_types::commutative;
 418         }
 419         return (*seq.begin()).rest.return_type();
 420 }
 421
 422 unsigned add::return_type_tinfo(void) const
 423 {
 424         if (seq.size()==0) {
 425                 return tinfo_key;
 426         }
 427         return (*seq.begin()).rest.return_type_tinfo();
 428 }
 429
 430 ex add::thisexpairseq(const epvector & v, const ex & oc) const
 431 {
 432         return (new add(v,oc))->setflag(status_flags::dynallocated);
 433 }
 434
 435 ex add::thisexpairseq(epvector * vp, const ex & oc) const
 436 {
 437         return (new add(vp,oc))->setflag(status_flags::dynallocated);
 438 }
 439
 440 expair add::split_ex_to_pair(const ex & e) const
 441 {
 442         if (is_ex_exactly_of_type(e,mul)) {
 443                 const mul & mulref = ex_to_mul(e);
 444                 ex numfactor = mulref.overall_coeff;
 445                 // mul * mulcopyp = static_cast<mul *>(mulref.duplicate());
 446                 mul * mulcopyp = new mul(mulref);
 447                 mulcopyp->overall_coeff = _ex1();
 448                 mulcopyp->clearflag(status_flags::evaluated);
 449                 mulcopyp->clearflag(status_flags::hash_calculated);
 450                 return expair(mulcopyp->setflag(status_flags::dynallocated),numfactor);
 451         }
 452         return expair(e,_ex1());
 453 }
 454
 455 expair add::combine_ex_with_coeff_to_pair(const ex & e,
 456                                                                                   const ex & c) const
 457 {
 458         GINAC_ASSERT(is_ex_exactly_of_type(c, numeric));
 459         if (is_ex_exactly_of_type(e, mul)) {
 460                 const mul &mulref = ex_to_mul(e);
 461                 ex numfactor = mulref.overall_coeff;
 462                 mul *mulcopyp = new mul(mulref);
 463                 mulcopyp->overall_coeff = _ex1();
 464                 mulcopyp->clearflag(status_flags::evaluated);
 465                 mulcopyp->clearflag(status_flags::hash_calculated);
 466                 mulcopyp->setflag(status_flags::dynallocated);
 467                 if (are_ex_trivially_equal(c, _ex1())) {
 468                         return expair(*mulcopyp, numfactor);
 469                 } else if (are_ex_trivially_equal(numfactor, _ex1())) {
 470                         return expair(*mulcopyp, c);
 471                 }
 472                 return expair(*mulcopyp, ex_to_numeric(numfactor).mul_dyn(ex_to_numeric(c)));
 473         } else if (is_ex_exactly_of_type(e, numeric)) {
 474                 if (are_ex_trivially_equal(c, _ex1()))
 475                         return expair(e, _ex1());
 476                 return expair(ex_to_numeric(e).mul_dyn(ex_to_numeric(c)), _ex1());
 477         }
 478         return expair(e, c);
 479 }
 480
 481 expair add::combine_pair_with_coeff_to_pair(const expair & p,
 482                                                                                         const ex & c) const
 483 {
 484         GINAC_ASSERT(is_ex_exactly_of_type(p.coeff,numeric));
 485         GINAC_ASSERT(is_ex_exactly_of_type(c,numeric));
 486
 487         if (is_ex_exactly_of_type(p.rest,numeric)) {
 488                 GINAC_ASSERT(ex_to_numeric(p.coeff).is_equal(_num1())); // should be normalized
 489                 return expair(ex_to_numeric(p.rest).mul_dyn(ex_to_numeric(c)),_ex1());
 490         }
 491
 492         return expair(p.rest,ex_to_numeric(p.coeff).mul_dyn(ex_to_numeric(c)));
 493 }
 494
 495 ex add::recombine_pair_to_ex(const expair & p) const
 496 {
 497         if (ex_to_numeric(p.coeff).is_equal(_num1()))
 498                 return p.rest;
 499         else
 500                 return p.rest*p.coeff;
 501 }
 502
 503 ex add::expand(unsigned options) const
 504 {
 505         if (flags & status_flags::expanded)
 506                 return *this;
 507
 508         epvector * vp = expandchildren(options);
 509         if (vp==0)
 510                 return *this;
 511
 512         return (new add(vp,overall_coeff))->setflag(status_flags::expanded | status_flags::dynallocated);
 513 }
 514
 515 //////////
 516 // static member variables
 517 //////////
 518
 519 // protected
 520
 521 unsigned add::precedence = 40;
 522
 523 #ifndef NO_NAMESPACE_GINAC
 524 } // namespace GiNaC
 525 #endif // ndef NO_NAMESPACE_GINAC