Talk:Polytree

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A problem with definitions

The first paragraph of this article allows the underlying undirected graph to be disconnected. However other parts of the paper assume it is connected, such as the alternative name "oriented tree" and the OEIS listing. McKay (talk) 05:48, 10 August 2012 (UTC)[reply]

I notice that has been fixed. Zaslav (talk) 22:27, 9 January 2013 (UTC)[reply]

@David Eppstein: The messages above pertain to something that was already fixed 9 years ago. Why did you put them back? Dr. Universe (talk) 02:01, 27 June 2022 (UTC)[reply]

@Dr. Universe: You should not remove comments from talk pages. You may be blocked for this behavior. Don't do it. See Wikipedia:Talk page guidelines, and particularly WP:ARCHIVENOTDELETE. Some talk pages have archives for old talk comments, when there are so many that they make it difficult to find current conversations, but this one is not very cluttered. —David Eppstein (talk) 06:38, 27 June 2022 (UTC)[reply]

@David Eppstein:I've finally got around to reading those two WP pages. I wonder if there's ever been any precedent for blocking someone for deleting talk comments? It seems a bit extreme to say that I "may be blocked" for it when I wasn't aware of those two WP pages before, and I was genuinely just trying to clean up the talk page a bit. May I create a new heading for the issues being discussed below? This would separate the above discussion which was already resolved, from the below discussions which are still on-going. Dr. Universe (talk) 18:35, 3 July 2022 (UTC)[reply]

Of course you're not going to be blocked for doing it once or twice without knowing you shouldn't. It's after you have been warned not to do it tha it becomes problematic. That's what the warning is for. Yes, new threads should have new titles, but it seems we only have old threads here. —David Eppstein (talk) 05:06, 4 July 2022 (UTC)[reply]

@David Eppstein: Thanks for the reply. I didn't see it until now because there was no ping. I came to this talk page because I'm seeing "directed tree" and "oriented tree" more often in the literature than "polytree". The article also says that polytree is one of the newer definitions. I deleted the above conversation because that part was already resolved, and I wanted to shift focus more towards the discussions below, which I think are still important to resolve. Can we "archive" the above discussion (up to here) and keep the two comments that are below, so that they can be seen more clearly and hopefully lead to more discussion? I know that there's not been any discussion since 2013, but I would reply to those comments with my own thoughts, and encourage others to discuss too. Dr. Universe (talk) 19:31, 21 July 2022 (UTC)[reply]

I put the simplest name "oriented tree" first. (I also wonder how many graph theorists use the name "polytree"?) Zaslav (talk) 22:30, 9 January 2013 (UTC)[reply]

I find this confusing: In other words, it is a directed graph with exactly one directed path between any two vertices;. What is meant is an undirected path (i.e. a path in the undirected tree), isn't it? Below there is talk of an undirected cycle to refer to a cycle in the undirected graph, so the adjectives seem to be used in different senses here. — Preceding unsigned comment added by 2.230.4.151 (talk) 13:12, 11 May 2013 (UTC)[reply]