*SignumFn* | *documentation* (*SignumFn* ?NUMBER) denotes the sign of ?NUMBER. This is one of the following values: -1, 1, or 0 | |

**has axiom** (=> (*equal* (*RemainderFn* ?NUMBER1 ?NUMBER2) ?NUMBER) (*equal* (*SignumFn* ?NUMBER2) (*SignumFn* ?NUMBER)))
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**has axiom** (=> (*instance* ?NUMBER NegativeRealNumber) (*equal* (*SignumFn* ?NUMBER) -1))
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**has axiom** (=> (*instance* ?NUMBER NonnegativeRealNumber) (or (*equal* (*SignumFn* ?NUMBER) 1) (*equal* (*SignumFn* ?NUMBER) 0)))
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**has axiom** (=> (*instance* ?NUMBER PositiveRealNumber) (*equal* (*SignumFn* ?NUMBER) 1))
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**has domain1** RealNumber | |

**has ***range* Integer | |

**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 | |