L = koszulDual(Q)
The input $Q$ is a quotient of a polynomial algebra by a quadratic ideal (which might be 0). Some of the variables may be declared as SkewCommutative. Moreover, the variables may have multi-degrees where the first degree is equal to $1$. The quadratic ideal must be homogeneous with respect to the multi-degree and the "skew-degree". The output is the Lie algebra whose enveloping algebra is the Koszul dual of $Q$.
|
|
|
|
|
|
Here is an example of a non-Koszul algebra. The table for the Ext-algebra has a non-zero occurrence off the diagonal.
|
|
|
|
|
|
The object koszulDual is a method function.