| slovo | definícia |
logic programming
(encz) | logic programming, n: |
logic programming
(wn) | logic programming
n 1: a computer language designed in Europe to support natural
language processing [syn: Prolog, logic programing,
logic programming]
2: creating a program that enables the computer to reason
logically [syn: logic programming, logic programing] |
logic programming
(foldoc) | logic programming
A
declarative, relational style of programming based on
first-order logic. The original logic programming language
was Prolog. The concept is based on Horn clauses.
The programmer writes a "database" of "facts", e.g.
wet(water).
("water is wet") and "rules", e.g.
mortal(X) :- human(X).
("X is mortal is implied by X is human"). Facts and rules are
collectively known as "clauses".
The user supplies a "goal" which the system attempts to
prove using "resolution" or "backward chaining". This
involves matching the current goal against each fact or the
left hand side of each rule using "unification". If the
goal matches a fact, the goal succeeds; if it matches a rule
then the process recurses, taking each sub-goal on the right
hand side of the rule as the current goal. If all sub-goals
succeed then the rule succeeds.
Each time a possible clause is chosen, a "choice point" is
created on a stack. If subsequent resolution fails then
control eventually returns to the choice point and subsequent
clauses are tried. This is known as "backtracking".
Clauses may contain logic variables which take on any value
necessary to make the fact or the left hand side of the rule
match a goal. Unification binds these variables to the
corresponding subterms of the goal. Such bindings are
associated with the choice point at which the clause was
chosen and are undone when backtracking reaches that choice
point.
The user is informed of the success or failure of his first
goal and if it succeeds and contains variables he is told what
values of those variables caused it to succeed. He can then
ask for alternative solutions.
(1997-07-14)
|
| | podobné slovo | definícia |
logic programming
(encz) | logic programming, n: |
logic programming
(wn) | logic programming
n 1: a computer language designed in Europe to support natural
language processing [syn: Prolog, logic programing,
logic programming]
2: creating a program that enables the computer to reason
logically [syn: logic programming, logic programing] |
constraint logic programming
(foldoc) | Constraint Logic Programming
(CLP) A programming framework based (like Prolog)
on LUSH (or SLD) resolution, but in which unification has
been replaced by a constraint solver. A CLP interpreter
contains a Prolog-like inference engine and an {incremental
constraint solver}. The engine sends constraints to the solver
one at a time. If the new constraint is consistent with the
collected constraints it will be added to the set. If it is
inconsistent, it will cause the engine to backtrack.
CLP* is a variant.
["Constraint Logic Programming", J. Jaffar et al, 14th POPL,
ACM 1987].
(1994-11-01)
|
distributed logic programming
(foldoc) | Distributed Logic Programming
(DLP) A logic programming language similar to
Prolog, combined with parallel object orientation similar
to POOL. DLP supports distributed backtracking over the
results of a rendezvous between objects. Multi-threaded
objects have autonomous activity and may simultaneously
evaluate method calls.
["DLP: A Language for Distributed Logic Programming",
A. Eliens, Wiley 1992].
(1996-01-07)
|
logic programming
(foldoc) | logic programming
A
declarative, relational style of programming based on
first-order logic. The original logic programming language
was Prolog. The concept is based on Horn clauses.
The programmer writes a "database" of "facts", e.g.
wet(water).
("water is wet") and "rules", e.g.
mortal(X) :- human(X).
("X is mortal is implied by X is human"). Facts and rules are
collectively known as "clauses".
The user supplies a "goal" which the system attempts to
prove using "resolution" or "backward chaining". This
involves matching the current goal against each fact or the
left hand side of each rule using "unification". If the
goal matches a fact, the goal succeeds; if it matches a rule
then the process recurses, taking each sub-goal on the right
hand side of the rule as the current goal. If all sub-goals
succeed then the rule succeeds.
Each time a possible clause is chosen, a "choice point" is
created on a stack. If subsequent resolution fails then
control eventually returns to the choice point and subsequent
clauses are tried. This is known as "backtracking".
Clauses may contain logic variables which take on any value
necessary to make the fact or the left hand side of the rule
match a goal. Unification binds these variables to the
corresponding subterms of the goal. Such bindings are
associated with the choice point at which the clause was
chosen and are undone when backtracking reaches that choice
point.
The user is informed of the success or failure of his first
goal and if it succeeds and contains variables he is told what
values of those variables caused it to succeed. He can then
ask for alternative solutions.
(1997-07-14)
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