*AbsoluteValueFn* | *documentation* The value of (*AbsoluteValueFn* ?NUMBER) is the absolute value of the RealNumber ?NUMBER | |

**has axiom** (*<=>* (*equal* (*AbsoluteValueFn* ?NUMBER1) ?NUMBER2) (or (*and* (*instance* ?NUMBER1 PositiveInteger) (*equal* ?NUMBER1 ?NUMBER2)) (*and* (*instance* ?NUMBER1 NegativeInteger) (*equal* ?NUMBER2 (*SubtractionFn* 0 ?NUMBER1)))))
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**has domain1** RealNumber | |

**has ***range* PositiveRealNumber | |

**is an ***instance* of UnaryFunction | |

BinaryRelation | **is first ***domain* of *DomainFn* | |

**is first ***domain* of *equivalenceRelationOn* | |

**is first ***domain* of *inverse* | |

**is first ***domain* of *irreflexiveOn* | |

**is first ***domain* of *partialOrderingOn* | |

**is first ***domain* of *RangeFn* | |

**is first ***domain* of *reflexiveOn* | |

**is first ***domain* of *totalOrderingOn* | |

**is first ***domain* of *trichotomizingOn* | |

**is second ***domain* of *inverse* | |

Function | **is first ***domain* of *AssignmentFn* | |

**is first ***domain* of *closedOn* | |

**is first ***domain* of *range* | |

**is first ***domain* of *rangeSubclass* | |

Class | **is third ***domain* of *domain* | |

**is third ***domain* of *domainSubclass* | |

Abstract | **is ***disjoint* from Physical | |