Construction of Elements

Contents

Zero(L) : AlgLie -> AlgLieElt
Zero(L) : AlgMatLie -> AlgMatLieElt
L ! 0 : AlgLie, RngIntElt -> AlgLieElt
L ! 0 : AlgMatLie, RngIntElt -> AlgMatLieElt
The zero element of the Lie algebra L.
Random(L) : AlgLie -> AlgLieElt
Random(L) : AlgMatLie -> AlgMatLieElt
Given a Lie algebra L defined over a finite ring, a random element is returned.

Construction of Elements of Structure Constant Algebras

elt<L | r1, r2, ..., rn> : AlgLie, RngElt, RngElt, ..., RngElt -> AlgLieElt
Given a Lie algebra L of dimension n over a ring R, and ring elements r1, r2, ..., rn ∈R construct the element r1 * e1 + r2 * e2 + ... + rn * en of L.
L ! Q : AlgLie, SeqEnum[RngElt] -> AlgLieElt
Given a Lie algebra L of dimension n and a sequence Q = [r1, r2, ..., rn] of elements of the base ring R of L, the element r1 * e1 + r2 * e2 + ... + rn * en of L is constructed.
BasisProduct(L, i, j) : AlgLie, RngIntElt, RngIntElt -> AlgLieElt
Returns the product of the i-th and j-th basis element of the Lie algebra L.
BasisProducts(L) : AlgLie -> SeqEnum
    Rep: MonStgElt                      Default: "Dense"
Returns the products of all basis elements of the Lie algebra L.

The optional parameter Rep may be used to specify the format of the result. If Rep is set to "Dense", the products are returned as a sequence Q of n sequences of n elements of L, where n is the dimension of L. The element Q[i][j] is the product of the i-th and j-th basis elements.

If Rep is set to "Sparse", the products are returned as a sequence Q containing quadruples (i, j, k, aijk) signifying that the product of the i-th and j-th basis elements is ∑k=1n aijk bk, where bk is the k-th basis element and n = dim(L).

Construction of Matrix Elements

Matrix Lie elements can be constructed using the functions below. For more information on constructing matrices see Section Construction of a Matrix.

elt<R | L> : AlgMatLie, [ RngElt ] -> AlgMatLieElt
elt<R | L> : AlgMatLie, RngElt, ..., RngElt -> AlgMatLieElt
R ! L : AlgMatLie, [RngElt] -> AlgMatLieElt
Create the element of the matrix Lie algebra R of degree n whose entries are the n2 elements of the sequence L.
DiagonalMatrix(L, Q) : AlgMatLie, [RngElt] -> AlgMatLieElt
Diagonal matrix in the matrix Lie algebra L, given by the sequence Q of ring elements.
ScalarMatrix(L, r) : AlgMatLie, RngElt -> AlgMatLieElt
Scalar matrix in the matrix Lie algebra L, defined by the ring element r.
V2.28, 13 July 2023