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GradedLieAlgebras :: signExtLie

signExtLie -- returns the sign of a basis element in the Ext-algebra

Synopsis

Description

i1 : L=lieAlgebra({a,b,c},genSigns=>{0,0,1},genWeights=>{{1,0},{1,0},{2,1}},diffl=>true)

o1 = L

o1 : LieAlgebra
i2 : L=diffLieAlgebra{L.zz,L.zz,a b}/{a a b, b b a}

o2 = L

o2 : LieAlgebra
i3 : extBasisLie 3

o3 = {ext , ext , ext , ext , ext }
         0     1     2     3     4

o3 : List
i4 : L.cache.extRepRing

o4 = QQ[ext , ext , ext , ext , ext ]
           0     1     2     3     4

o4 : PolynomialRing
i5 : signExtLie ext_3

o5 = 0
i6 : weightExtLie ext_3

o6 = {3, 2}

o6 : List
i7 : extTableLie 3

o7 = | 2 0 0 |
     | 0 1 2 |
     | 0 0 0 |

              3        3
o7 : Matrix ZZ  <--- ZZ

See also

Ways to use signExtLie :