Dictionary method model_site.adp_matrix_beta does not compile

[jamesrhester]

Error is:

failed to compile defn meth. _model_site.adp_matrix_beta

 [label,symop] =   _model_site.id

 a = atom_site[label]
 s = space_group_symop[SymKey(symop)]

 _model_site.adp_matrix_beta =  s.R * a.tensor_beta * s.RT

TypeError: basis is undefined

[jamesrhester]

This error occurs because the system fails to pick up the internal typing of _model_site.id. By changing the dictionary definition to _type.purpose Encode, _type.contents Text and _type.dimension [2], the routine compiles normally. I think we should abandon trying to specify the internal types of lists in such detail.