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The languages like GOEDEL, ALF, LIFE etc. are currently more oriented to theory than to real-world applications. In real-life usage, we can give more chances to CLP which is sometimes ASSUMED as a PROLOG lifesaver for practical applications.

The languages like Goedel, ALF, LIFE etc. are currently more oriented to theory than to real-world applications. In real-life usage, we can give more chances to CLP which is sometimes assumed as a PROLOG lifesaver for practical applications.

CLP(X) uses "INTERPRETABLE" domain X, e.g., reals, integers, STRINGS, while pure Prolog is limited to "uninterpretable" Herbrand Universe. Also, Prolog uses UNIFICATION as a main data OPERATION while CLP allows declarative constraints which are more general than unification.

CLP(X) uses "interpretable" domain X, e.g., reals, integers, strings, while pure Prolog is limited to "uninterpretable" Herbrand Universe. Also, Prolog uses unification as a main data operation while CLP allows declarative constraints which are more general than unification.

Using the TECHNIQUE known as meta-programming, it is POSSIBLE to IMPLEMENT CLP completely in PROLOG. The disadvantage of this approach is DEGRADATION of PERFORMANCE that is typical for meta-programming.

Using the technique known as meta-programming, it is possible to implement CLP completely in PROLOG. The disadvantage of this approach is degradation of performance that is typical for meta-programming.

CLP is an extension of PROLOG (logic PROGRAMMING) where the UNIFICATION is substituted by solving equalities and other types of constraints over particular domain like reals, INTEGERS, strings ETC. 

CLP is an extension of PROLOG (logic programming) where the unification is substituted by solving equalities and other types of constraints over particular domain like reals, integers, strings etc. 

Meta-PROGRAM is a program that USES other program as its data. For EXAMPLE, meta-INTERPRETER of a given PROGRAMMING language is an interpreter of that language written in the same language.

Meta-program is a program that uses other program as its data. For example, meta-interpreter of a given programming language is an interpreter of that language written in the same language.

It is EASY to WRITE a COMPLETE PROLOG interpreter in PROLOG with DIFFERENT behaviour via meta-programming technique.

It is easy to write a complete PROLOG interpreter in PROLOG with different behaviour via meta-programming technique.

You can find PROLOG in AREAS like EXPERT systems or theorem provers construction. The VARIANT of PROLOG CALLED DATALOG is used in database management.

You can find PROLOG in areas like expert systems or theorem provers construction. The variant of PROLOG called DATALOG is used in database management.

Prolog SEEMS to be good for problems in which logic is intimately involved, or whose SOLUTIONS have a logical characterization. Like other INTERACTIVE, symbolic languages, Prolog is also good for rapid prototyping.

Prolog seems to be good for problems in which logic is intimately involved, or whose solutions have a logical characterization. Like other interactive, symbolic languages, Prolog is also good for rapid prototyping.

Here is an Example:

SUPPOSE we WANT to ask, “What course does ROBIN teach”?,then we can write it in prolog as

” Is there a course,X,that ROBIN teaches? “

Here,

here x stands for an object that the questioner does not know about yet,so to answer the prolog has to find the value of x.If we know the value of variable then it is KNOWN as BOUND, if we don’t know then known as UNBOUND.

Here is an Example:

Suppose we want to ask, “What course does ROBIN teach”?,then we can write it in prolog as

” Is there a course,x,that ROBIN teaches? “

Here,

here x stands for an object that the questioner does not know about yet,so to answer the prolog has to find the value of x.If we know the value of variable then it is known as BOUND, if we don’t know then known as UNBOUND.

In Prolog, procedures are called predicate. FOLLOWING are the TWO reasons because of which it is also KNOWN as procedural language. The two UNUSUAL ASPECTS of Prolog are:

• prolog has assign-once variables.
• Prolog is non deterministic.

In Prolog, procedures are called predicate. Following are the two reasons because of which it is also known as procedural language. The two unusual aspects of Prolog are:

Following are the data types supported by prolog :Prolog’s single data type is the TERM. Terms are either atoms, numbers, variables or compound terms.

• ATOM : An atom is a general-purpose name with no INHERENT meaning.
• NUMBERS : Numbers are like integers,float etc.
• VARIABLES : Are denoted string consisting of letters, numbers, underscore characters, and beginning with an upper-case letter or underscore.
• COMPOUND TERMS : A compound term is composed of an atom CALLED a “functor” and a number of “arguments”, which are again terms. They are written by SEPARATING them by commas.

Following are the data types supported by prolog :Prolog’s single data type is the term. Terms are either atoms, numbers, variables or compound terms.

Here is an example. of SAMPLE programming LANGUAGE by displaying the message “Hello”:

SOURCE CODE :
// the main program (this is a comment)
Hello:-
nl,
WRITE(‘Hello !’ ).
}

Here is an example. of Sample programming language by displaying the message “Hello”:

SOURCE CODE :
// the main program (this is a comment)
Hello:-
nl,
write(‘Hello !’ ).
}

Following are some POINTS for using prolog more:

• SWI-Prolog is free, open-source, and very well maintained.
• It’s much much easier to distribute SWI-Prolog applications than Java ones
• Prolog is much less verbose,which is helpful when during development.
• Prolog ALLOWS one to define any WORD or collection of “symbol characters” (e.g. >>, +, /, , //, :===/===: ) as an infix, postfix, or prefix operator.
• In Prolog, you can treat data as programs.
• Prolog is interactive.

Following are some points for using prolog more:

Following are some areas in which prolog is used:

• intelligent data base retrieval
• NATURAL language UNDERSTANDING
• EXPERT systems
• specification language
• machine learning
• robot planning
• AUTOMATED reasoning
• problem solving

Following are some areas in which prolog is used:

Following are the features of PROLOG language:

• Intelligent Systems – programs which perform useful tasks by utilizing artificial INTELLIGENCE techniques.
• Expert Systems – intelligent systems which reproduce decision-making at the LEVEL of a human expert.
• Natural Language Systems – which can analysis and respond to statements made in ordinary language as opposed to approved keywords or menu SELECTIONS.
• Relational Database Systems.

Following are the features of prolog language:

SWI-PROLOG is a free prolog COMPILER licensed under GPL, targeting primarily the RESEARCH and education.

SWI-Prolog is a free prolog compiler licensed under GPL, targeting primarily the research and education.

In any LANGUAGE, a FUNCTION that can CALL itself until the goal has been succeed is REFERRED as recursion. In Prolog, recursion happens when a predicate contains a goal that refers to itself.

In any language, a function that can call itself until the goal has been succeed is referred as recursion. In Prolog, recursion happens when a predicate contains a goal that refers to itself.

In Prolog, backtracking is a process ADOPTED by Prolog. When a sub-goal fails in Prolog, the Prolog SYSTEM moves its steps backwards to the previous goal and tries to re-satisfy it. Backtracking ENABLES Prolog to find all alternative solutions to a GIVEN QUERY.

In Prolog, backtracking is a process adopted by Prolog. When a sub-goal fails in Prolog, the Prolog system moves its steps backwards to the previous goal and tries to re-satisfy it. Backtracking enables Prolog to find all alternative solutions to a given query.

In Prolog, in order to PROCESS the elements of a LIST, we have to match them to variables. The method for doing is

• We get the HEAD by matching it to a variable.
• By CALLING a predicate with the variable, it processes the head.
• Until you get an empty list REPEAT the above steps.

In Prolog, in order to process the elements of a list, we have to match them to variables. The method for doing is

Prolog: It is a “declarative PROGRAMMING” language which means that you have to SPECIFY the goals, but not the strategy to REACH the goal. It figures it out on its own.
Normal Programming language: Languages like C/C++/Java/Python are IMPERATIVE (IP) languages that does specify instructions of how to reach some goal, but leaving the REAL goal implicit

Prolog: It is a “declarative programming” language which means that you have to specify the goals, but not the strategy to reach the goal. It figures it out on its own.
Normal Programming language: Languages like C/C++/Java/Python are imperative (IP) languages that does specify instructions of how to reach some goal, but leaving the real goal implicit

The “=” OPERATOR in Prolog is actually a predicate that stands for UNIFICATION. This operator “= =” means the two terms are not IDENTICAL. Unification does not take PLACE even if this SUCCEEDS.

The “=” operator in Prolog is actually a predicate that stands for unification. This operator “= =” means the two terms are not identical. Unification does not take place even if this succeeds.

Cut function is USED in Prolog when you want to restrict Prolog from backtracking into certain choicepoints or subgoals, either because the alternatives would give wrong solutions or for efficiency REASONS.

Advantage of using cut in Prolog is :

• Through cut, we can often improve the efficiency of the program
• We can SPECIFY EXCLUSIVE RULES using cut

Cut function is used in Prolog when you want to restrict Prolog from backtracking into certain choicepoints or subgoals, either because the alternatives would give wrong solutions or for efficiency reasons.

Advantage of using cut in Prolog is :

Member is a PROLOG tool that is USED for CONFIGURING lists and to INTRODUCE the IDEA of recursing down lists.

Member is a Prolog tool that is used for configuring lists and to introduce the idea of recursing down lists.

• “=” TRIGGERS UNIFICATION in PROLOG
• “is” triggers ARITHMETIC EVALUATION in Prolog

In Prolog, DATA and program both are implemented as the bunch of trees. There is no difference between a rule that CAUSES OPERATIONS to happen and a rule that just gives BACK a data value.

In Prolog, data and program both are implemented as the bunch of trees. There is no difference between a rule that causes operations to happen and a rule that just gives back a data value.

Operator + can be used to negate goals; these are EITHER sub-goals in the body of a rule or sub-goals of a QUERY. We cannot negate facts or the HEADS of rules.

Operator + can be used to negate goals; these are either sub-goals in the body of a rule or sub-goals of a query. We cannot negate facts or the heads of rules.

A PROLOG list is referred as an ORDERED sequence of elements of arbitrary LENGTH. Here the elements are variables, CONSTANT, structures, INCLUDING other lists.

A Prolog list is referred as an ordered sequence of elements of arbitrary length. Here the elements are variables, constant, structures, including other lists.

When running the subgoals in a RULE’s body, the PARENT goal is referred to the goal that CAUSED the matching of the HEAD of the CURRENT rule.

When running the subgoals in a rule’s body, the parent goal is referred to the goal that caused the matching of the head of the current rule.

In Prolog, procedures are referred as predicate. It is ALSO KNOWN as a PROCEDURAL language due to the two UNUSUAL aspects of prolog LIKE prolog is non deterministic and has assign- once variables.

In Prolog, procedures are referred as predicate. It is also known as a procedural language due to the two unusual aspects of prolog like prolog is non deterministic and has assign- once variables.

In Prolog, “SETOF” predicate can be used to FIND out all the solutions of a predicate. For example, you have this database:

Wisdom (SAP, Testing Tools)
Wisdom (PHP, PERL)
And if you want to find the solutions of Wisdom(X, Y). We can enter
Setof ([ X,Y] ,Wisdom (X,Y), Z).
Z = [[ SAP , Testing Tools], [ PHP, Perl] ]

In Prolog, “Setof” predicate can be used to find out all the solutions of a predicate. For example, you have this database:

Wisdom (SAP, Testing Tools)
Wisdom (PHP, Perl)
And if you want to find the solutions of Wisdom(X, Y). We can enter
Setof ([ X,Y] ,Wisdom (X,Y), Z).
Z = [[ SAP , Testing Tools], [ PHP, Perl] ]

Prolog programming language is used in sectors like

• Automated REASONING
• MACHINE learning
• Robot planning
• Problem SOLVING
• Natural language UNDERSTANDING
• Intelligent DATA base retrieval
• Expert systesm

Prolog programming language is used in sectors like

Setof/3 is SIMILAR to bagof/3 and the DIFFERENCE between is that bagof/3 LEAVES all REPEATED SOLUTIONS while setof/3 removes them.

Setof/3 is similar to bagof/3 and the difference between is that bagof/3 leaves all repeated solutions while setof/3 removes them.

Prolog is designed for Artificial Intelligence, and it deals with the declarative and logical ASPECTS. Prolog is a logic programming and is based on three ATTRIBUTES- Facts, Rules of INFERENCE and Questions. Facts are the KNOWN truths, rules determine how NEW information can be inferred from these facts, and questions search for answers according to the facts and rules.

Prolog is designed for Artificial Intelligence, and it deals with the declarative and logical aspects. Prolog is a logic programming and is based on three attributes- Facts, Rules of Inference and Questions. Facts are the known truths, rules determine how new information can be inferred from these facts, and questions search for answers according to the facts and rules.