ToCanonical

• ToCanonical[expr] gives a canonical reorganization of the indices of expr according to the symmetries of tensors and positions of dummies.

• This function is in charge of everything related to canonicalization in the system, and constitutes the most sophisticated part of xTensor`.
• When there is a metric and a derivative which is not compatible with that metric, ToCanonical changes to the slower, but more careful algorithm (private) ToCanonicalDers. This change can be forbidden with the global variable $MixedDers.
• Options:
MathLink            False        change to the fast external canonicalizer
UseMetricOnVBundle    All        which indices can be raised and lowered
GivePerm            False        permutation giving the canonical form
Notation            Images    notation for the canonical permutation
ExpandChristoffel    False        convert Christoffels into metric derivatives
Verbose            False        global information on the canonicalization
• See: Section 7.2.
• See also: SymmetryOf, xSort, Simplification.
• New in version 0.
• Last update: 27-IX-2007 for version 0.9.3 of xTensor`.

Created by Mathematica  (May 16, 2008)