* Implementation of GiNaC's non-commutative products of expressions. */
/*
- * GiNaC Copyright (C) 1999-2003 Johannes Gutenberg University Mainz, Germany
+ * GiNaC Copyright (C) 1999-2005 Johannes Gutenberg University Mainz, Germany
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <algorithm>
#include "mul.h"
#include "matrix.h"
#include "archive.h"
+#include "indexed.h"
#include "utils.h"
namespace GiNaC {
GINAC_IMPLEMENT_REGISTERED_CLASS_OPT(ncmul, exprseq,
print_func<print_context>(&ncmul::do_print).
- print_func<print_tree>(&basic::do_print_tree).
+ print_func<print_tree>(&ncmul::do_print_tree).
print_func<print_csrc>(&ncmul::do_print_csrc).
print_func<print_python_repr>(&ncmul::do_print_csrc))
ex ncmul::expand(unsigned options) const
{
// First, expand the children
- exvector expanded_seq = expandchildren(options);
+ std::auto_ptr<exvector> vp = expandchildren(options);
+ const exvector &expanded_seq = vp.get() ? *vp : this->seq;
// Now, look for all the factors that are sums and remember their
// position and number of terms.
}
// If there are no sums, we are done
- if (number_of_adds == 0)
- return (new ncmul(expanded_seq, true))->
- setflag(status_flags::dynallocated | (options == 0 ? status_flags::expanded : 0));
+ if (number_of_adds == 0) {
+ if (vp.get())
+ return (new ncmul(vp))->
+ setflag(status_flags::dynallocated | (options == 0 ? status_flags::expanded : 0));
+ else
+ return *this;
+ }
// Now, form all possible products of the terms of the sums with the
// remaining factors, and add them together
intvector k(number_of_adds);
+ /* Rename indices in the static members of the product */
+ exvector expanded_seq_mod;
+ size_t j = 0;
+ size_t i;
+ for (i=0; i<expanded_seq.size(); i++) {
+ if (i == positions_of_adds[j]) {
+ expanded_seq_mod.push_back(_ex1);
+ j++;
+ } else {
+ expanded_seq_mod.push_back(rename_dummy_indices_uniquely(ncmul(expanded_seq_mod), expanded_seq[i]));
+ }
+ }
+
while (true) {
- exvector term = expanded_seq;
- for (size_t i=0; i<number_of_adds; i++)
- term[positions_of_adds[i]] = expanded_seq[positions_of_adds[i]].op(k[i]);
+ exvector term = expanded_seq_mod;
+ for (i=0; i<number_of_adds; i++) {
+ term[positions_of_adds[i]] = rename_dummy_indices_uniquely(ncmul(term), expanded_seq[positions_of_adds[i]].op(k[i]));
+ }
+
distrseq.push_back((new ncmul(term, true))->
setflag(status_flags::dynallocated | (options == 0 ? status_flags::expanded : 0)));
int ncmul::degree(const ex & s) const
{
+ if (is_equal(ex_to<basic>(s)))
+ return 1;
+
// Sum up degrees of factors
int deg_sum = 0;
exvector::const_iterator i = seq.begin(), end = seq.end();
int ncmul::ldegree(const ex & s) const
{
+ if (is_equal(ex_to<basic>(s)))
+ return 1;
+
// Sum up degrees of factors
int deg_sum = 0;
exvector::const_iterator i = seq.begin(), end = seq.end();
ex ncmul::coeff(const ex & s, int n) const
{
+ if (is_equal(ex_to<basic>(s)))
+ return n==1 ? _ex1 : _ex0;
+
exvector coeffseq;
coeffseq.reserve(seq.size());
return (new ncmul(vp))->setflag(status_flags::dynallocated);
}
+ex ncmul::conjugate() const
+{
+ if (return_type() != return_types::noncommutative) {
+ return exprseq::conjugate();
+ }
+
+ if ((return_type_tinfo() & 0xffffff00U) != TINFO_clifford) {
+ return exprseq::conjugate();
+ }
+
+ exvector ev;
+ ev.reserve(nops());
+ for (const_iterator i=end(); i!=begin();) {
+ --i;
+ ev.push_back(i->conjugate());
+ }
+ return (new ncmul(ev, true))->setflag(status_flags::dynallocated).eval();
+}
+
// protected
/** Implementation of ex::diff() for a non-commutative product. It applies
++i;
}
// all factors checked
- GINAC_ASSERT(!all_commutative); // not all factors should commute, because this is a ncmul();
+ GINAC_ASSERT(!all_commutative); // not all factors should commutate, because this is a ncmul();
return all_commutative ? return_types::commutative : return_types::noncommutative;
}
// non-virtual functions in this class
//////////
-exvector ncmul::expandchildren(unsigned options) const
+std::auto_ptr<exvector> ncmul::expandchildren(unsigned options) const
{
- exvector s;
- s.reserve(seq.size());
- exvector::const_iterator it = seq.begin(), itend = seq.end();
- while (it != itend) {
- s.push_back(it->expand(options));
- it++;
+ const_iterator cit = this->seq.begin(), end = this->seq.end();
+ while (cit != end) {
+ const ex & expanded_ex = cit->expand(options);
+ if (!are_ex_trivially_equal(*cit, expanded_ex)) {
+
+ // copy first part of seq which hasn't changed
+ std::auto_ptr<exvector> s(new exvector(this->seq.begin(), cit));
+ reserve(*s, this->seq.size());
+
+ // insert changed element
+ s->push_back(expanded_ex);
+ ++cit;
+
+ // copy rest
+ while (cit != end) {
+ s->push_back(cit->expand(options));
+ ++cit;
+ }
+
+ return s;
+ }
+
+ ++cit;
}
- return s;
+
+ return std::auto_ptr<exvector>(0); // nothing has changed
}
const exvector & ncmul::get_factors() const
git://www.ginac.de / ginac.git / blobdiff