Properties of Boolean functions/soft

Studies of Boolean functions
Properties of
Boolean functions
hard soft
binary binary
integer integer

Soft properties depend on the arity of the BF.

twin

The Zhegalkin twin of a BF is its Zhegalkin index interpreted as a truth table of length 2arity.

half-complement

The half-complement of a BF is its XOR with xarity1.   See e.g. the half-complements of :

  • arity 3:             0001 0001 XOR 0000 1111 = 0001 1110
  • arity 4:             0001 0001 0001 0001 XOR 0000 0000 1111 1111 = 0001 0001 1110 1110

ultra equivalence classes

The two families on the left form a super-family.
The family on the right is a super-family on its own.
Together these two super-families form an ultra-family.

Families and clans can be merged with their complements, which creates super-families and super-clans.
Further merging them with their half-complements creates ultra-families and ultra-clans.
This family is a complete ultra-family: 1100 1010     (So its matrix of truth tables is mirror symmetric.)
(Factions do not have a unique half-complement, so there are no ultra-factions.)

tribe

For a given arity the tribe is the next biggest equivalence class after the ultra-clan.
Blunt BF belong to tribes denoted by their consul weight. All sharp BF belong to a tribe on their own.

principalities and dominions

A principality is a set of n-ary BF whose (n+1)-ary noble equivalents form a faction. Dominions are closely related.

partner and friend

The partner/friend of a BF differs from its truth table in the least/most significant bit.
E.g. 0110 has the partner 1110 and the friend 0111.

squad, platoon and company

squad: union of a super-faction and its partner   (always two super-factions, i.e. four factions)
platoon: union of a squad and its twin   (one or two squads, i.e. four or eight factions)
company: union of a platoon and its friend   (one or two platoons)

Category:Properties of Boolean functions
Category:Properties of Boolean functions