# dual(MonomialIdeal,RingElement) -- the Alexander dual

## Synopsis

• Function: dual
• Usage:
dual(I,m)
• Inputs:
• I, , a monomial ideal
• m, , a monomial
• Optional inputs:
• Outputs:
• the Alexander dual of I formed with respect to m.

## Description

The monomial m should be divisible by all of the minimal generators of I.