# map(LieDerivation) -- get the map in the definition of a Lie derivation

## Description

The optional inputs given above are not relevant for Lie algebras. If $d$ is a derivation $M \ \to\ L$, then there is defined a Lie algebra map $f: M \ \to\ L$, which determines the $M$-module-structure on $L$, and this map is represented by map(d).

 i1 : L=lieAlgebra({x,y},Signs=>1) o1 = L o1 : LieAlgebra i2 : M=lieAlgebra({a,b},Signs=>0,Weights=>{2,2}) o2 = M o2 : LieAlgebra i3 : f = map(L,M,{x x,x y}) o3 = f o3 : LieAlgebraMap i4 : d = lieDerivation(f,{2 x,-y}) o4 = d o4 : LieDerivation i5 : describe d o5 = a => 2 x b => - y map => f sign => 1 weight => {-1, 0} source => M target => L i6 : d a b o6 = 0 o6 : L