Wikidata:Property proposal/Crossing number
crossing number
editOriginally proposed at Wikidata:Property proposal/Natural science
Description | Crossing number for mathematical knots; the crossing number of a knot is the smallest number of crossings of any diagram of the knot. It is a knot invariant. |
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Represents | crossing number (Q2548661) |
Data type | String |
Domain | knot (Q1188853), link (Q1760728) |
Allowed values | 0|[1-9][0-9]* |
Example 1 | unknot (Q1188344) → 0 |
Example 2 | trefoil knot (Q168620) → 3 |
Example 3 | figure-eight knot (Q168697) → 4 |
Example 4 | Kinoshita–Terasaka knot (Q94827585) → 11 |
Source | https://knotinfo.math.indiana.edu/ |
Planned use | to add these values to entries for knots on Wikidata |
Expected completeness | always incomplete (Q21873886) |
See also | Dowker-Thistlethwaite notation (P8378) |
Single-value constraint | yes |
Wikidata project | WikiProject Mathematics (Q8487137) |
Motivation
editThis is a mathematical invariant for knots. While this is available in external databases, it also belongs here on Wikidata. The Anome (talk) 12:27, 13 July 2022 (UTC)
Discussion
editNotified participants of WikiProject Mathematics
- Support ArthurPSmith (talk) 20:52, 13 July 2022 (UTC)
- @The Anome: can you describe in more detail in the description what it means to be a "Crossing number"? ChristianKl ❪✉❫ 15:29, 19 July 2022 (UTC)
- @ChristianKl: Yes: see en:Crossing_number_(knot_theory) The Anome (talk) 18:34, 19 July 2022 (UTC)
- @The Anome: I want more detail in the description, so that people who see the property on Wikidata have a better idea of what it's about. It doesn't help me at all to read the Wikipedia article for that purpose. ChristianKl ❪✉❫ 09:15, 20 July 2022 (UTC)
- @ChristianKl: I've modified the description in the proposal above. I hope that's sufficient; if not, please let me know. The Anome (talk) 14:15, 20 July 2022 (UTC)
- Great. Support ChristianKl ❪✉❫ 20:53, 20 July 2022 (UTC)
- @ChristianKl: I've modified the description in the proposal above. I hope that's sufficient; if not, please let me know. The Anome (talk) 14:15, 20 July 2022 (UTC)
- @The Anome: I want more detail in the description, so that people who see the property on Wikidata have a better idea of what it's about. It doesn't help me at all to read the Wikipedia article for that purpose. ChristianKl ❪✉❫ 09:15, 20 July 2022 (UTC)
- @ChristianKl: Yes: see en:Crossing_number_(knot_theory) The Anome (talk) 18:34, 19 July 2022 (UTC)
Update: I've added a domain restriction, to just mathematical knots and links (and knots are of course a subset of links, but I thought I'd be explicit). Rationale: there is another concept of crossing number, en:Crossing number (graph theory), for graphs, but I think it's sufficiently different that we might want to make this a separate property. The Anome (talk) 10:27, 22 July 2022 (UTC)
- @The Anome, ArthurPSmith, ChristianKl: Done --Tinker Bell ★ ♥ 01:14, 4 September 2022 (UTC)
- Fabulous. I will generate the appropriate data tables and submit them to QuickStatements. The Anome (talk) 14:29, 7 September 2022 (UTC)