# Complex reflection groups¶

class sage.categories.complex_reflection_groups.ComplexReflectionGroups(s=None)

The category of complex reflection groups.

Let $$V$$ be a complex vector space. A complex reflection is an element of $$\operatorname{GL}(V)$$ fixing an hyperplane pointwise and acting by multiplication by a root of unity on a complementary line.

A complex reflection group is a group $$W$$ that is (isomorphic to) a subgroup of some general linear group $$\operatorname{GL}(V)$$ generated by a distinguished set of complex reflections.

The dimension of $$V$$ is the rank of $$W$$.

For a comprehensive treatment of complex reflection groups and many definitions and theorems used here, we refer to [LT2009]. See also Wikipedia article Reflection_group.

ReflectionGroup() for usage examples of this category.

EXAMPLES:

sage: from sage.categories.complex_reflection_groups import ComplexReflectionGroups
sage: ComplexReflectionGroups()
Category of complex reflection groups
sage: ComplexReflectionGroups().super_categories()
[Category of complex reflection or generalized coxeter groups]
sage: ComplexReflectionGroups().all_super_categories()
[Category of complex reflection groups,
Category of complex reflection or generalized coxeter groups,
Category of groups,
Category of monoids,
Category of finitely generated semigroups,
Category of semigroups,
Category of finitely generated magmas,
Category of inverse unital magmas,
Category of unital magmas,
Category of magmas,
Category of enumerated sets,
Category of sets,
Category of sets with partial maps,
Category of objects]


An example of a reflection group:

sage: W = ComplexReflectionGroups().example(); W
5-colored permutations of size 3


W is in the category of complex reflection groups:

sage: W in ComplexReflectionGroups()
True

Finite
class ParentMethods

Bases: object

rank()

Return the rank of self.

The rank of self is the dimension of the smallest faithfull reflection representation of self.

EXAMPLES:

sage: W = CoxeterGroups().example(); W
The symmetric group on {0, ..., 3}
sage: W.rank()
3

additional_structure()

Return None.

Indeed, all the structure complex reflection groups have in addition to groups (simple reflections, …) is already defined in the super category.

EXAMPLES:

sage: from sage.categories.complex_reflection_groups import ComplexReflectionGroups

example()

Return an example of a complex reflection group.

EXAMPLES:

sage: from sage.categories.complex_reflection_groups import ComplexReflectionGroups
sage: ComplexReflectionGroups().example()
5-colored permutations of size 3

super_categories()

Return the super categories of self.

EXAMPLES:

sage: from sage.categories.complex_reflection_groups import ComplexReflectionGroups
sage: ComplexReflectionGroups().super_categories()
[Category of complex reflection or generalized coxeter groups]