SUNIndex[a]
is an index in the adjoint representation. If the argument is an integer, SUNIndex[a]
turns into ExplicitSUNIndex[a]
.
Overview, ExplicitSUNIndex, SUNDelta, SUNF.
[i] SUNIndex
[i] // StandardForm
SUNIndex
(*SUNIndex[i]*)
[2] SUNIndex
[2] // StandardForm
SUNIndex
(*ExplicitSUNIndex[2]*)
[i, j] // FCI // StandardForm
SUNDelta
(*SUNDelta[SUNIndex[i], SUNIndex[j]]*)