If I is an ideal, then toDual(d,I) = inverseSystem(d, I). See the documentation of InverseSystems for the basic theory and of inverseSystem for the function.

If I is a matrix, then the code first replaces it with the ideal generated by the entries.

The Base ring of the input must be a standard graded polynomial ring over a field.

- InverseSystems -- Macaulay's Inverse Systems
- inverseSystem -- Inverse systems with equivariance
- fromDual -- Ideal from inverse system

- toDual(ZZ,Ideal)
- toDual(ZZ,Matrix)