26 Numerics library [numerics]

26.2 Definitions [numerics.defns]

Define GENERALIZED_NONCOMMUTATIVE_SUM(op, a1, ..., aN) as follows:

  • a1 when N is 1, otherwise

  • op(GENERALIZED_NONCOMMUTATIVE_SUM(op, a1, ..., aK),
    op(GENERALIZED_NONCOMMUTATIVE_SUM(op, aM, ..., aN)) for any K where 1 < K+1 = MN.

Define GENERALIZED_SUM(op, a1, ..., aN) as GENERALIZED_NONCOMMUTATIVE_SUM(op, b1, ..., bN) where b1, ..., bN may be any permutation of a1, ..., aN.