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Posets :: meetExists

meetExists -- determines if the meet exists for two elements of a poset



The meet of $a$ and $b$ in $P$, if it exists, is the unique greatest element less than both $a$ and $b$.

i1 : P = poset {{a,b}, {a,c}, {b,d}, {c,d}, {e,d}};
i2 : meetExists(P, b, c)

o2 = true
i3 : meetExists(P, b, e)

o3 = false
i4 : Q = poset {{a,b}, {a,c}, {d,b}, {d,c}, {b,e}, {c,e}};
i5 : meetExists(Q, b, c)

o5 = false

See also

Ways to use meetExists :

For the programmer

The object meetExists is a method function.