ginac/add.cpp

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