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isLattice -- determines if a poset is a lattice

Synopsis

Description

This function examines the entire poset to determine whether or not every pair of elements has both a meet and a join.
i1 : P = poset ({a,b,c,d,e,f}, {(a,d),(d,f),(b,d),(b,e),(c,e),(e,f)});
i2 : isLattice (P)

o2 = false
And by adding an element to the above example, we can create a poset which is a lattice.
i3 : P = poset ({a,b,c,d,e,f,x}, {(a,d),(d,f),(b,d),(b,e),(c,e),(e,f), (x,a), (x,b), (x,c)});
i4 : isLattice (P)

o4 = true

Ways to use isLattice :