> By the way, anyone already knows how to handle to symmetry group of tensor indices in the case of an index disappearing?
>>> V.symmetry TensorSymmetry((0, 1), (Permutation(0, 1)(3, 4), Permutation(1, 2)(3, 4))) >>> tensor_gens(V.symmetry.base, V.symmetry.generators, [[0]], 0)[1:] ([1], [Permutation(1, 2)(3, 4)]) >>> tensor_gens(V.symmetry.base, V.symmetry.generators, [[1]], 0)[1:] ([0], [Permutation(0, 2)(3, 4)]) On Thursday, September 19, 2013 8:59:12 PM UTC+2, F. B. wrote: > > I am considering introducing numeric indices for tensor expressions. My > basic idea is that > > > - setting a numeric index is like working on a specific basis for that > index. > - setting it breaks the symmetry group of tensor indices, creating a > new tensor with an index missing (replaced by a fixed number). > - numeric indices can be numbers and symbols. > > By the way, anyone already knows how to handle to symmetry group of tensor > indices in the case of an index disappearing? > -- You received this message because you are subscribed to the Google Groups "sympy" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/sympy. For more options, visit https://groups.google.com/groups/opt_out.
