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Is it always acyclic though? https://stackoverflow.com/questions/6163683/cycles-in-family-tree-software https://stackoverflow.com/questions/6163683/cycles-in-fa

Is it always acyclic though? https://stackoverflow.com/questions/6163683/cycles-in-family-tree-software https://stackoverflow.com/questions/6163683/cycles-in-family...

slavik81 7y ago
Yes. You cannot be your own ancestor. A graph pointing from child to parent can split and merge, but never loop. Though, you may need a cyclic directed graph for fictional family trees and time travel paradoxes.
- tgv 7y ago
  And data entry errors...
- rhn_mk1 7y ago
  A family tree is an overloaded term. The tree of ancestry, which describes who beget whom, sure cannot be cyclical. The graph of civil relationships can certainly contain cycles. If the relationship in question is "is a legal parent of", for example, then adopt your parent. The opportunities for cycles multiply if both blood and legal relationships are taken into account.
  - Retric 7y ago
    For an actual example, Woody Allen’s marriage to his adopted daughter essentially resulted in her being her own mother.
    - barrkel 7y ago
      To be clear, Allen never adopted Soon-Yi Previn; she was adopted by Mia Farrow and Andre Previn before Farrow & Allen got together.
      - Retric 7y ago
        Yea, it’s also not the best example because Mia Farrow was not legally wed though Allen was in a long term relation and they had a child. So, I am not sure if it qualified as a common law marriage before their separation. In an August 1992 interview with Time Magazine Allen said, “I am not Soon-Yi's father or stepfather”, adding, “I’ve never even lived with Mia. I've never in my entire life slept at Mia's apartment, and I never even used to go over there until my children came along seven years ago. I never had any family dinners over there. I was not a father to her adopted kids in any sense of the word.” Adding that Soon-Yi never treated him as a father figure and that he rarely spoke to her before the affair, Allen seemed to see few issues with their relationship.[196]. https://en.wikipedia.org/wiki/Woody_Allen https://en.wikipedia.org/wiki/Woody_Allen However, if your mapping out relationships in software without considering the timeline it looks like a circular relationship. Further, I am sure you can find cases that are actually incestuous.
  - lidHanteyk 7y ago
    So don't mix those two things, then; keep them distinct. Work to preserve the acyclic property, rather than trying to toss new concepts in.
    - rhn_mk1 7y ago
      This works only until the concepts are the reason the problem is being tackled. A family tree based only on genetic relationships is interesting to few people outside geneticists and doctors. Most people are interested in familial ties as they are culturally defined.
  - deleted 7y ago
    [deleted]

Is it always acyclic though? https://stackoverflow.com/questions/6163683/cycles-in-family-tree-software https://stackoverflow.com/questions/6163683/cycles-in-family...

slavik81 7y ago

Yes. You cannot be your own ancestor. A graph pointing from child to parent can split and merge, but never loop. Though, you may need a cyclic directed graph for fictional family trees and time travel paradoxes.

tgv 7y ago
And data entry errors...
rhn_mk1 7y ago
A family tree is an overloaded term. The tree of ancestry, which describes who beget whom, sure cannot be cyclical. The graph of civil relationships can certainly contain cycles. If the relationship in question is "is a legal parent of", for example, then adopt your parent. The opportunities for cycles multiply if both blood and legal relationships are taken into account.
- Retric 7y ago
  For an actual example, Woody Allen’s marriage to his adopted daughter essentially resulted in her being her own mother.
  - barrkel 7y ago
    To be clear, Allen never adopted Soon-Yi Previn; she was adopted by Mia Farrow and Andre Previn before Farrow & Allen got together.
    - Retric 7y ago
      Yea, it’s also not the best example because Mia Farrow was not legally wed though Allen was in a long term relation and they had a child. So, I am not sure if it qualified as a common law marriage before their separation. In an August 1992 interview with Time Magazine Allen said, “I am not Soon-Yi's father or stepfather”, adding, “I’ve never even lived with Mia. I've never in my entire life slept at Mia's apartment, and I never even used to go over there until my children came along seven years ago. I never had any family dinners over there. I was not a father to her adopted kids in any sense of the word.” Adding that Soon-Yi never treated him as a father figure and that he rarely spoke to her before the affair, Allen seemed to see few issues with their relationship.[196]. https://en.wikipedia.org/wiki/Woody_Allen https://en.wikipedia.org/wiki/Woody_Allen However, if your mapping out relationships in software without considering the timeline it looks like a circular relationship. Further, I am sure you can find cases that are actually incestuous.
- lidHanteyk 7y ago
  So don't mix those two things, then; keep them distinct. Work to preserve the acyclic property, rather than trying to toss new concepts in.
  - rhn_mk1 7y ago
    This works only until the concepts are the reason the problem is being tackled. A family tree based only on genetic relationships is interesting to few people outside geneticists and doctors. Most people are interested in familial ties as they are culturally defined.
- deleted 7y ago
  [deleted]