Version 1 (modified by onnopaap, 14 years ago)


Base Template DifferenceOf2Classes

DifferenceOf2Classes is a template for expressing that a class is the difference, as given in ISO 15926-2, of two classes.

DifferenceOf2Classes(a, b, c) means that c is the difference of a and b.

1 hasClass1 Class
2 hasClass2 Class
3 hasClassDifference Class


DifferenceOf2Classes(x1, x2, x3) <-> 
Class(x1) & 
Class(x2) & 
Class(x3) & 
exists y(EnumeratedSetOf2Classes(x1, x2, y) & 
DifferenceOfSetOfClassTemplate(y, x3)) . 

NOTE ISO 15926-2 defines the difference of two classes a and b as (a [ b)n(a \ b). See 8.3 for further information on the representation used in this template.

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