FindBlockedIndices

• FindBlockedIndices[expr] gives an IndexList with the blocked indices (i.e. those indices which cannot represent contractions) which are present in expr.

• FindBlockedIndices always returns a list of indices with head IndexList, to avoid confusion with the notation for basis and component indices.
• Indices in expressions with free ultraindices and indices in Scalar expressions or scalar-functions are not found.
• FindBlockedIndices has attribute HoldFirst, and hence requires very often the use of Evaluate.
• Currently indices of types C (component-indices), D (directional indices) and L (labels) are blocked indices.
• See: Section 2.7.
• See also: FindIndices, FindFreeIndices, FindDummyIndices.
• New in version 0.
• Last update: 15-V-2008 for version 0.9.5 of xTensor`.

Created by Mathematica  (May 16, 2008)