Question

Write the following statements as Prolog clauses, in the order given: If it is raining or snowing, then there is precipitation. If it is freezing and there is precipitation, then it is snowing. If it is not freezing and there is precipitation, then it is raining. It is snowing. What answer does Prolog give to the following queries: Is it freezing

Answer 1

Answer:

a. See Explanation Below

b. No

Explanation:

a.

Interpreting the statements line by line.

First, the prolog clauses need to be initialised, as follows:

:- dynamic freezing/0, precipitation/0, snowing/0, raining/0.

If it is raining or snowing, then there is precipitation.

The statement is splited in two.

1st, if it is raining then there is precipitation

Or

2nd, if it is raining, then there is precipitation.

So, both statements are given as:

precipitation :- raining.

precipitation :- snowing.

If it is freezing and there is precipitation, then it is snowing.

This is a conditional statement that checks if it is freezing AND there's is precipitation.

If true, then it is snowing.

The above statement is given as:

snowing :- freezing, precipitation.

If it is not freezing and there is precipitation, then it is raining.

This is a conditional statement that checks if it is not freezing AND there's is precipitation.

If true, then it is raining.

The not clause is represented as \+

The above statement is the given as:

raining :- \+ freezing, precipitation.

It is snowing.

This is represented as follows

snowing.

So, the full prolog clause is as follows

:- dynamic freezing/0, precipitation/0, snowing/0, raining/0.

precipitation :- raining.

precipitation :- snowing.

snowing :- freezing, precipitation.

raining :- \+ freezing, precipitation.

snowing.

b. What answer does Prolog give to the following queries:

Is it freezing

No

Reason;

All of the conditions above point to raining or snowing; none points to freezing.

Hence, it is no.