Revision history [back]

Suppose C is a full dimensional pointed rational polyhedral cone with vertex at the origin. Then there is a correspondence between faces of C and faces of C.dual() given by

F -> Fd := { y in C.dual() | <y, x> = 0 for all x in F}

This correspondence satisfies

dim(F)+dim(Fd)=dim(C)

I want to define the function in sage that maps each face in C.face_lattice() to its corresponding face in C.dual().face_lattice(). Does this function exist in sage?

Suppose C is a full dimensional pointed rational polyhedral cone with vertex at the origin. Then there is a correspondence between faces of C and faces of C.dual() given by

F -> Fd := { y in C.dual() | <y, x> = 0 for all x in F}
F }

This correspondence satisfies

dim(F)+dim(Fd)=dim(C)

I want to define the function (or dictionary) in sage that maps each face in C.face_lattice() to its corresponding face in C.dual().face_lattice(). Does this function exist in sage?