7 Mar 1998 22:41:17 -0500

Related articles |
---|

terminology: double-rooted DAG? markh@usai.asiainfo.com (Mark Harrison) (1998-03-03) |

Re: terminology: double-rooted DAG? mfinney@inmind.com (1998-03-06) |

Re: terminology: double-rooted DAG? dwight@pentasoft.com (1998-03-06) |

Re: terminology: double-rooted DAG? vladimir@cs.ualberta.ca (Vladimir Alexiev) (1998-03-07) |

Re: terminology: double-rooted DAG? markh@usai.asiainfo.com (Mark Harrison) (1998-03-07) |

Re: terminology: double-rooted DAG? mfinney@inmind.com (1998-03-08) |

From: | Vladimir Alexiev <vladimir@cs.ualberta.ca> |

Newsgroups: | comp.compilers |

Date: | 7 Mar 1998 22:41:17 -0500 |

Organization: | University of Alberta, Computing Science |

References: | 98-03-021 98-03-042 |

Keywords: | theory |

In-reply-to: | mfinney@inmind.com's message of 6 Mar 1998 16:48:42 -0500 |

mfinney@inmind.com writes:

*> :>1. It always has a defined root node (like a tree), and*

*> :>2. There is also a "tail" node*

*> Its called a "lattice". One of the definitions of a lattice is that it*

*> is a dag which contains both a least upper bound and greatest lower*

*> bound -- precisely what you have described.*

No, because he never stated that his DAG is to be interpreted as a

partial order. In other words, a DAG is not necessarily transitive,

and we don't know if transitive edges are assumed, either.

The correct answer is: who cares :-) Now, if he had asked about some

algorithms that might be applicable to some problem on such a

structure, it would matter...

--

Post a followup to this message

Return to the
comp.compilers page.

Search the
comp.compilers archives again.