* Implementation of GiNaC's indices. */
/*
- * 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 <iostream>
GINAC_IMPLEMENT_REGISTERED_CLASS_OPT(varidx, idx,
print_func<print_context>(&varidx::do_print).
- // print_latex inherited from idx
+ print_func<print_latex>(&varidx::do_print_latex).
print_func<print_tree>(&varidx::do_print_tree))
GINAC_IMPLEMENT_REGISTERED_CLASS_OPT(spinidx, varidx,
ex idx::map(map_function & f) const
{
- idx *copy = duplicate();
- copy->setflag(status_flags::dynallocated);
- copy->clearflag(status_flags::hash_calculated);
- copy->value = f(value);
- return *copy;
+ const ex &mapped_value = f(value);
+ if (are_ex_trivially_equal(value, mapped_value))
+ return *this;
+ else {
+ idx *copy = duplicate();
+ copy->setflag(status_flags::dynallocated);
+ copy->clearflag(status_flags::hash_calculated);
+ copy->value = mapped_value;
+ return *copy;
+ }
}
/** Returns order relation between two indices of the same type. The order