Monomial bases

This page documents the methods that have a monomial basis as their input. For methods that have a monomial basis as their output, see Computing monomial bases.

polytope_of_essential_exponentsFunction

polytopeofessential_exponents(basis::MonomialBasis)

Return the polytope of essential exponents corresponding to the monomial basis, i.e. the convex hull of exponent vectors of all occurring monomials. This is only possible if the basis was computed with compute_polytope = true.

Examples

julia> basis = basis_lie_highest_weight(:A, 3, [1,1,1]; monomial_ordering = :deglex,  compute_polytope = true)
Monomial basis of a highest weight module
  of highest weight w_1 + w_2 + w_3
  of dimension 64
  with monomial ordering deglex([x1, x2, x3, x4, x5, x6])
over abstract Lie algebra of type A3 over QQ
where the used birational sequence consists of the following roots:
  [a_1, a_2, a_3, a_1 + a_2, a_2 + a_3, a_1 + a_2 + a_3]

julia> polytope_of_essential_exponents(basis)
Polyhedron in ambient dimension 6
Experimental

This function is part of the experimental code in Oscar. Please read here for more details.

source