31 lines
549 B
Plaintext
31 lines
549 B
Plaintext
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/* Ellipses are defined by centre and semi-axes */
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:- object(ellipse(_Center, _A, _B)).
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:- info([
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authors is 'Paulo Moura',
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version is 1.0,
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date is 2000/4/22,
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comment is 'Parametric object for representing geometric ellipses.',
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parnames is ['Center', 'Rx', 'Ry'],
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source is 'Example adopted from the POEM system by Ben Staveley-Taylor.']).
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:- public(area/1).
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:- mode(area(-number), one).
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area(Area) :-
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pi(Pi),
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parameter(2, A),
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parameter(3, B),
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Area is Pi*A*B.
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pi(3.14196).
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:- end_object.
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