30 Aug
2006
30 Aug
'06
12:08 p.m.
Dear Alexei, On Tue, 29 Aug 2006, Sheplyakov Alexei wrote:
This simple program
[...]
fails (both with GiNaC 1.4 CVS and 1.3.x). I believe that the reason is bug in indexed.cpp:reposition_dummy_indices() and propose attached patch to fix it. Note that patch *seems* to be correct, but IMHO it is somewhat ugly and probably inefficient. Could anyone suggest a better solution?
What if we simply don't do this kind of toggling of the variance in the case that both indices of the dummy pair belong to the same indexed object and the indexed object has a symmetry in which the dummy pair is involved? Seems simpler to me. Best wishes, Chris