Associative algebras

class sage.categories.associative_algebras.AssociativeAlgebras(base_category)

Bases: sage.categories.category_with_axiom.CategoryWithAxiom_over_base_ring

The category of associative algebras over a given base ring.

An associative algebra over a ring R is a module over R which is also a not necessarily unital ring.

Warning

Until trac ticket #15043 is implemented, Algebras is the category of associative unital algebras; thus, unlike the name suggests, AssociativeAlgebras is not a subcategory of Algebras but of MagmaticAlgebras.

EXAMPLES:

sage: from sage.categories.associative_algebras import AssociativeAlgebras
sage: C = AssociativeAlgebras(ZZ); C
Category of associative algebras over Integer Ring

TESTS:

sage: from sage.categories.magmatic_algebras import MagmaticAlgebras
sage: C is MagmaticAlgebras(ZZ).Associative()
True
sage: TestSuite(C).run()
class ElementMethods

An abstract class for elements of an associative algebra.

Note

Magmas.Element.__mul__ is preferable to Modules.Element.__mul__ since the later does not handle products of two elements of self.

TESTS:

sage: A = AlgebrasWithBasis(QQ).example(); A
An example of an algebra with basis: the free algebra
on the generators ('a', 'b', 'c') over Rational Field
sage: x = A.an_element()
sage: x
B[word: ] + 2*B[word: a] + 3*B[word: b] + B[word: bab]
sage: x.__mul__(x)
B[word: ] + 4*B[word: a] + 4*B[word: aa] + 6*B[word: ab]
+ 2*B[word: abab] + 6*B[word: b] + 6*B[word: ba]
+ 2*B[word: bab] + 2*B[word: baba] + 3*B[word: babb]
+ B[word: babbab] + 9*B[word: bb] + 3*B[word: bbab]
AssociativeAlgebras.Unital

alias of Algebras