logic variable

logic variable

A variable in a logic programming language which is initially undefined ("unbound") but may get bound to a value or another logic variable during unification of the containing clause with the current goal. The value to which it is bound may contain other variables which may themselves be bound or unbound.

For example, when unifying the clause

sad(X) :- computer(X, ibmpc).

with the goal


the variable X will become bound to the atom "billgates" yielding the new subgoal "computer(billgates, ibmpc)".
This article is provided by FOLDOC - Free Online Dictionary of Computing (foldoc.org)
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In the future, k-value logic will be used to express the logic variable more effectively.
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In Figure 4, the logic variable for pipes entering zone 1 is presented.
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