eps is a Levi-Civita symbol.

Be careful, LeviCivita is not part of sympy.tensor.tensor, and is not 
designed to interoperate with that module.

Also consider that you are defining a Lorentz tensor index type as a 3 
dimensional Euclidean index type.

I just noticed that the Kronecker delta is not filled with components data. 
Opened an issue:
https://github.com/sympy/sympy/issues/8743

On Friday, January 2, 2015 10:59:13 PM UTC+1, Chaffra Affouda wrote:
>
> How do I implement the Levi-Civita and Kroenecker tensors in sympy? I am 
> doing
>
> from sympy.tensor.tensor import TensorIndexType, tensor_indices
> from sympy.tensor.tensor import tensorhead, TensorManager
> from sympy.tensor.tensor import get_symmetric_group_sgs
> from sympy import LeviCivita
>
> Lorentz = TensorIndexType('Lorentz',
>                           dim=3,
>                           eps_dim=3,
>                           metric=False,
>                           dummy_fmt='L')
>
>
>
> Lorentz.data = [1,1,1]
>
>
> Lorentz.epsilon.data = [[[LeviCivita(i,j,k) for k in range(3)] 
>                          for j in range(3)] 
>                         for i in range(3)]
>
> i,j,k,l,m, n = tensor_indices('i,j,k,l,m,n', Lorentz)
>
> eps = Lorentz.epsilon
> delta = Lorentz.delta
>
> Is this correct?
>

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