
 Operations on Associative Algebras and their Elements 
  Given an associative algebra A and a subalgebra B of A, compute the idealizer of B in A, that is, the largest subalgebra of A in which B is an ideal. 
  Let A and B be subalgebras of an associative algebra with underlying module M. This function returns the submodule of M which is spanned by the elements [a, b] = a * b  b * a, a in A, b in B. CommutatorIdeal(A, B) : AlgAss, AlgAss > AlgAss 
  For two subalgebras A and B of an associative algebra, return the left annihilator of B in A; that is, the subalgebra of A consisting of all elements a such that a * b = 0 for all b in B. RightAnnihilator(A, B) : AlgAss, AlgAss > AlgAss, AlgAss 
 www.umich.edu /~gpcc/scs/magma/text894.htm (718 words) 
