Hello!
This simple program fails:
#include <iostream>
#include <cassert>
#include <ginac/ginac.h>
using namespace std;
using namespace GiNaC;
int main(int argc, char** argv)
{
varidx mu1(symbol("mu1"), 4);
varidx mu2(symbol("mu2"), 4);
varidx mu3(symbol("mu3"), 4);
varidx mu4(symbol("mu4"), 4);
varidx mu5(symbol("mu5"), 4);
varidx mu6(symbol("mu6"), 4);
symbol A("A");
exvector ev2;
ev2.push_back(mu3.toggle_variance());
ev2.push_back(mu6);
ev2.push_back(mu5.toggle_variance());
ev2.push_back(mu6.toggle_variance());
ev2.push_back(mu5);
ev2.push_back(mu3);
ex test_cycl = indexed(A, sy_cycl(), ev2);
test_cycl = test_cycl.simplify_indexed();
assert(test_cycl.get_free_indices().size() == 0);
return 0;
}
The reason is that reposition_dummy_indices() (indexed.cpp:639) ignores
symmetry properties of expression[s]. To be more specific, if the
expression e has some symmetry properties, than the code like this
(indexed.cpp:654):
e = e.subs(lst(
*it2 == ex_to<varidx>(*it2).toggle_variance(),
ex_to<varidx>(*it2).toggle_variance() == *it2
), subs_options::no_pattern);
can yield some non-trivial permutation of indices (apart from swapping
covariant and contravariant instances of some index), so subsequent
manipulations become incorrect. However, I don't know how to fix this.
Any ideas?
--
All science is either physics or stamp collecting.