# Region Connection Calculus 2¶

## Description¶

*Region Connection Calculus* (RCC) [1] [2] is intended to serve for qualitative spatial representation and reasoning. RCC abstractly describes regions (in Euclidean space, or in a topological space) by their possible relations to each other.

RCC2 is the simplest form of RCC and consists of 2 basic relations that are possible between two regions. It is a stripped down version of RCC8. The mapping from RCC8 to RCC2 can be seen below:

RCC8 | RCC2 |
---|---|

dc | dc |

ec | c |

po | |

tpp | |

ntpp | |

eq | |

tppi | |

ntppi |

## Relations¶

All the possible RCC5 relations between a blue object X and a red object Y are:

Relation | Illustration | Interpretation |
---|---|---|

X dc Y |
X is disconnected from Y. | |

X c Y |
X is connected to Y. | |

## References¶

[1] | Randell, D. A., Cui, Z. and Cohn, A. G.: A spatial logic based on regions and connection, Proc. 3rd Int. Conf. on Knowledge Representation and Reasoning, Morgan Kaufmann, San Mateo, pp. 165–176, 1992. (link) |

[2] | Anthony G. Cohn, Brandon Bennett, John Gooday, Micholas Mark Gotts: Qualitative Spatial Representation and Reasoning with the Region Connection Calculus. GeoInformatica, 1, 275–316, 1997. |