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GradedLieAlgebras :: basicExpressionLie

basicExpressionLie -- checks if a general Lie expression is of normal form

Synopsis

Description

An expression is a "basic Lie expression" if it is generalExpressionLie and is equal to its normalFormLie, which means that either it is [] or a basicMonomialLie or it is of the form {{coefs},{liemons}}, where coefs are non-zero elements in L.field (and not just a single 1) and liemons are basicMonomialLie, which means that they are basis vectors for the Lie algebra chosen by the program, see How to write Lie elements.

i1 : L = lieAlgebra({a,b,c},{},genSigns=>{1,1,0})

o1 = L

o1 : LieAlgebra
i2 : basicExpressionLie{{1,2},{[a,a,b],[a,c,c]}}

o2 = false
i3 : normalFormLie{{1,2},{[a,a,b],[a,c,c]}}

         1
o3 = {{- -}, {[b, a, a]}}
         2

o3 : List
i4 : basicExpressionLie oo

o4 = true
i5 : basicExpressionLie []

o5 = true
i6 : basicExpressionLie {{1},{[b,a,a]}}

o6 = false
i7 : normalFormLie {{1},{[b,a,a]}}

o7 = [b, a, a]

o7 : Array

See also