IndicesOf

• IndicesOf[selectors][expr] returns a list (head IndexList) of the indices in expression selected by the given selectors.

• A sequence of several selectors represents the And of all selectors (smaller result). A list of several selectors represents the Or of all selectors (bigger result).
• Possible selectors are:
    - Free: free indices
    - Dummy: dummy indices
    - Blocked: blocked indices
    - Up: contravariant indices
    - Down: covariant indices
    - AIndex: abstract indices
    - BIndex: basis indices
    - CIndex: component indices
    - DIndex: directional indices
    - LIndex: label indices:
    - Not[any of the previous]: complement of the previous
    - vbundle: indices of the given vbundle
    - basis: indices of the given basis
    - tensor: indices on the given tensor
    - covd: indices on the given covariant derivative
    - Basis[basis]: (both) indices on Basis objects of the given basis
• See: Section 2.7.
• See also: FindIndices, IsIndexOf.
• New in version 0.
• Last update: 24-IX-2007 for version 0.9.3 of xTensor`.

Created by Mathematica  (May 16, 2008)