3 * Implementation of GiNaC's simp_lor objects.
4 * No real implementation yet, to be done. */
7 * GiNaC Copyright (C) 1999-2000 Johannes Gutenberg University Mainz, Germany
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
38 #ifndef NO_NAMESPACE_GINAC
40 #endif // ndef NO_NAMESPACE_GINAC
43 // default constructor, destructor, copy constructor assignment operator and helpers
48 simp_lor::simp_lor() : type(invalid)
50 debugmsg("simp_lor default constructor",LOGLEVEL_CONSTRUCT);
51 tinfo_key=TINFO_simp_lor;
56 debugmsg("simp_lor destructor",LOGLEVEL_DESTRUCT);
60 simp_lor::simp_lor(const simp_lor & other)
62 debugmsg("simp_lor copy constructor",LOGLEVEL_CONSTRUCT);
66 const simp_lor & simp_lor::operator=(const simp_lor & other)
68 debugmsg("simp_lor operator=",LOGLEVEL_ASSIGNMENT);
78 void simp_lor::copy(const simp_lor & other)
85 void simp_lor::destroy(bool call_parent)
88 indexed::destroy(call_parent);
98 simp_lor::simp_lor(simp_lor_types const t) : type(t)
100 debugmsg("simp_lor constructor from simp_lor_types",LOGLEVEL_CONSTRUCT);
101 tinfo_key=TINFO_simp_lor;
104 simp_lor::simp_lor(simp_lor_types const t, const ex & i1, const ex & i2) :
105 indexed(i1,i2), type(t)
107 debugmsg("simp_lor constructor from simp_lor_types,ex,ex",LOGLEVEL_CONSTRUCT);
108 tinfo_key=TINFO_simp_lor;
109 GINAC_ASSERT(all_of_type_lorentzidx());
112 simp_lor::simp_lor(simp_lor_types const t, const string & n, const ex & i1) :
113 indexed(i1), type(t), name(n)
115 debugmsg("simp_lor constructor from simp_lor_types,string,ex",LOGLEVEL_CONSTRUCT);
116 tinfo_key=TINFO_simp_lor;
117 GINAC_ASSERT(all_of_type_lorentzidx());
120 simp_lor::simp_lor(simp_lor_types const t, const string & n, const exvector & iv) :
121 indexed(iv), type(t), name(n)
123 debugmsg("simp_lor constructor from simp_lor_types,string,exvector",LOGLEVEL_CONSTRUCT);
124 tinfo_key=TINFO_simp_lor;
125 GINAC_ASSERT(all_of_type_lorentzidx());
128 simp_lor::simp_lor(simp_lor_types const t, const string & n, exvector * ivp) :
129 indexed(ivp), type(t), name(n)
131 debugmsg("simp_lor constructor from simp_lor_types,string,exvector*",LOGLEVEL_CONSTRUCT);
132 tinfo_key=TINFO_simp_lor;
133 GINAC_ASSERT(all_of_type_lorentzidx());
137 // functions overriding virtual functions from bases classes
142 basic * simp_lor::duplicate() const
144 debugmsg("simp_lor duplicate",LOGLEVEL_DUPLICATE);
145 return new simp_lor(*this);
148 void simp_lor::printraw(ostream & os) const
150 debugmsg("simp_lor printraw",LOGLEVEL_PRINT);
151 os << "simp_lor(type=" << (unsigned)type
152 << ",name=" << name << ",indices=";
154 os << ",hash=" << hashvalue << ",flags=" << flags << ")";
157 void simp_lor::printtree(ostream & os, unsigned indent) const
159 debugmsg("simp_lor printtree",LOGLEVEL_PRINT);
160 os << string(indent,' ') << "simp_lor object: "
161 << "type=" << (unsigned)type
162 << ", name=" << name << ", ";
163 os << seq.size() << " indices" << endl;
164 printtreeindices(os,indent);
165 os << string(indent,' ') << "hash=" << hashvalue
166 << " (0x" << hex << hashvalue << dec << ")"
167 << ", flags=" << flags << endl;
170 void simp_lor::print(ostream & os, unsigned upper_precedence) const
172 debugmsg("simp_lor print",LOGLEVEL_PRINT);
182 os << "INVALID_SIMP_LOR_OBJECT";
188 void simp_lor::printcsrc(ostream & os, unsigned type, unsigned upper_precedence) const
190 debugmsg("simp_lor print csrc",LOGLEVEL_PRINT);
191 print(os,upper_precedence);
194 bool simp_lor::info(unsigned inf) const
196 return indexed::info(inf);
199 ex simp_lor::eval(int level) const
201 if (type==simp_lor_g) {
202 // canonicalize indices
204 int sig=canonicalize_indices(iv,false); // symmetric
206 // something has changed while sorting indices, more evaluations later
207 if (sig==0) return _ex0();
208 return ex(sig)*simp_lor(type,name,iv);
210 const lorentzidx & idx1=ex_to_lorentzidx(seq[0]);
211 const lorentzidx & idx2=ex_to_lorentzidx(seq[1]);
212 if ((!idx1.is_symbolic())&&(!idx2.is_symbolic())) {
213 // both indices are numeric
214 if ((idx1.get_value()==idx2.get_value())) {
216 if (idx1.get_value()==0) {
220 if (idx1.is_covariant()!=idx2.is_covariant()) {
221 // (_i,~i) or (~i,_i), i=1..3
224 // (_i,_i) or (~i,~i), i=1..3
229 // at least one off-diagonal
232 } else if (idx1.is_symbolic() &&
233 idx1.is_co_contra_pair(idx2)) {
234 return Dim()-idx1.get_dim_parallel_space();
243 int simp_lor::compare_same_type(const basic & other) const
245 GINAC_ASSERT(other.tinfo() == TINFO_simp_lor);
246 const simp_lor *o = static_cast<const simp_lor *>(&other);
249 return indexed::compare_same_type(other);
251 return name.compare(o->name);
253 return type < o->type ? -1 : 1;
256 bool simp_lor::is_equal_same_type(const basic & other) const
258 GINAC_ASSERT(other.tinfo() == TINFO_simp_lor);
259 const simp_lor *o = static_cast<const simp_lor *>(&other);
260 if (type!=o->type) return false;
261 if (name!=o->name) return false;
262 return indexed::is_equal_same_type(other);
265 unsigned simp_lor::return_type(void) const
267 return return_types::commutative;
270 unsigned simp_lor::return_type_tinfo(void) const
275 ex simp_lor::thisexprseq(const exvector & v) const
277 return simp_lor(type,name,v);
280 ex simp_lor::thisexprseq(exvector * vp) const
282 return simp_lor(type,name,vp);
286 // virtual functions which can be overridden by derived classes
292 // non-virtual functions in this class
297 bool simp_lor::all_of_type_lorentzidx(void) const
299 // used only inside of ASSERTs
300 for (exvector::const_iterator cit=seq.begin(); cit!=seq.end(); ++cit) {
301 if (!is_ex_of_type(*cit,lorentzidx)) return false;
307 // static member variables
316 const simp_lor some_simp_lor;
317 const type_info & typeid_simp_lor=typeid(some_simp_lor);
323 simp_lor lor_g(const ex & mu, const ex & nu)
325 return simp_lor(simp_lor::simp_lor_g,mu,nu);
328 simp_lor lor_vec(const string & n, const ex & mu)
330 return simp_lor(simp_lor::simp_lor_vec,n,mu);
333 ex simplify_simp_lor_mul(const ex & m, const scalar_products & sp)
335 GINAC_ASSERT(is_ex_exactly_of_type(m,mul));
336 exvector v_contracted;
338 // collect factors in an exvector, store squares twice
340 v_contracted.reserve(2*n);
341 for (unsigned i=0; i<n; ++i) {
343 if (is_ex_exactly_of_type(f,power)&&f.op(1).is_equal(_ex2())) {
344 v_contracted.push_back(f.op(0));
345 v_contracted.push_back(f.op(0));
347 v_contracted.push_back(f);
351 unsigned replacements;
352 bool something_changed=false;
354 exvector::iterator it=v_contracted.begin();
355 while (it!=v_contracted.end()) {
356 // process only lor_g objects
357 if (is_ex_exactly_of_type(*it,simp_lor) &&
358 (ex_to_simp_lor(*it).type==simp_lor::simp_lor_g)) {
359 const simp_lor & g=ex_to_simp_lor(*it);
360 GINAC_ASSERT(g.seq.size()==2);
361 const idx & first_idx=ex_to_lorentzidx(g.seq[0]);
362 const idx & second_idx=ex_to_lorentzidx(g.seq[1]);
363 // g_{mu,mu} should have been contracted in simp_lor::eval()
364 GINAC_ASSERT(!first_idx.is_equal(second_idx));
365 ex saved_g=*it; // save to restore it later
367 // try to contract first index
369 if (first_idx.is_symbolic()) {
370 replacements = subs_index_in_exvector(v_contracted,
371 first_idx.toggle_covariant(),second_idx);
372 if (replacements==0) {
373 // not contracted, restore g object
376 // a contracted index should occur exactly once
377 GINAC_ASSERT(replacements==1);
379 something_changed=true;
383 // try second index only if first was not contracted
384 if ((replacements==0)&&(second_idx.is_symbolic())) {
385 // first index not contracted, *it is again the original g object
386 replacements = subs_index_in_exvector(v_contracted,
387 second_idx.toggle_covariant(),first_idx);
388 if (replacements==0) {
389 // not contracted except in itself, restore g object
392 // a contracted index should occur exactly once
393 GINAC_ASSERT(replacements==1);
395 something_changed=true;
402 // process only lor_vec objects
403 bool jump_to_next=false;
404 exvector::iterator it1=v_contracted.begin();
405 while (it1!=v_contracted.end()-1) {
406 if (is_ex_exactly_of_type(*it1,simp_lor) &&
407 (ex_to_simp_lor(*it1).type==simp_lor::simp_lor_vec)) {
408 exvector::iterator it2=it1+1;
409 while ((it2!=v_contracted.end())&&!jump_to_next) {
410 if (is_ex_exactly_of_type(*it2,simp_lor) &&
411 (ex_to_simp_lor(*it2).type==simp_lor::simp_lor_vec)) {
412 const simp_lor & vec1=ex_to_simp_lor(*it1);
413 const simp_lor & vec2=ex_to_simp_lor(*it2);
414 GINAC_ASSERT(vec1.seq.size()==1);
415 GINAC_ASSERT(vec2.seq.size()==1);
416 const lorentzidx & idx1=ex_to_lorentzidx(vec1.seq[0]);
417 const lorentzidx & idx2=ex_to_lorentzidx(vec2.seq[0]);
418 if (idx1.is_symbolic() &&
419 idx1.is_co_contra_pair(idx2) &&
420 sp.is_defined(vec1,vec2)) {
421 *it1=sp.evaluate(vec1,vec2);
423 something_changed=true;
433 if (something_changed) {
434 return mul(v_contracted);
439 ex simplify_simp_lor(const ex & e, const scalar_products & sp)
441 // all simplification is done on expanded objects
442 ex e_expanded=e.expand();
444 // simplification of sum=sum of simplifications
445 if (is_ex_exactly_of_type(e_expanded,add)) {
447 for (unsigned i=0; i<e_expanded.nops(); ++i)
448 sum += simplify_simp_lor(e_expanded.op(i),sp);
453 // simplification of commutative product=commutative product of simplifications
454 if (is_ex_exactly_of_type(e_expanded,mul)) {
455 return simplify_simp_lor_mul(e,sp);
458 // cannot do anything
462 //ex Dim(void) // FIXME: what's going on here?
464 // static symbol * d=new symbol("dim");
472 void scalar_products::reg(const simp_lor & v1, const simp_lor & v2,
475 if (v1.compare_same_type(v2)>0) {
479 spm[make_key(v1,v2)]=sp;
482 bool scalar_products::is_defined(const simp_lor & v1, const simp_lor & v2) const
484 if (v1.compare_same_type(v2)>0) {
485 return is_defined(v2,v1);
487 return spm.find(make_key(v1,v2))!=spm.end();
490 ex scalar_products::evaluate(const simp_lor & v1, const simp_lor & v2) const
492 if (v1.compare_same_type(v2)>0) {
493 return evaluate(v2,v1);
495 return spm.find(make_key(v1,v2))->second;
498 void scalar_products::debugprint(void) const
500 cerr << "map size=" << spm.size() << endl;
501 for (spmap::const_iterator cit=spm.begin(); cit!=spm.end(); ++cit) {
502 const spmapkey & k=(*cit).first;
503 cerr << "item key=((" << k.first.first
504 << "," << k.first.second << "),";
505 k.second.printraw(cerr);
506 cerr << ") value=" << (*cit).second << endl;
510 spmapkey scalar_products::make_key(const simp_lor & v1, const simp_lor & v2)
512 GINAC_ASSERT(v1.type==simp_lor::simp_lor_vec);
513 GINAC_ASSERT(v2.type==simp_lor::simp_lor_vec);
514 lorentzidx anon=ex_to_lorentzidx(v1.seq[0]).create_anonymous_representative();
515 GINAC_ASSERT(anon.is_equal_same_type(ex_to_lorentzidx(v2.seq[0]).create_anonymous_representative()));
516 return spmapkey(strstrpair(v1.name,v2.name),anon);
519 #ifndef NO_NAMESPACE_GINAC
521 #endif // ndef NO_NAMESPACE_GINAC