Wikipedia:WikiProject Mathematics/PlanetMath Exchange/52-XX Convex and discrete geometry

This page provides a list of all articles available at PlanetMath in the following topic:

52-XX Convex and discrete geometry.

This list will be periodically updated. Each entry in the list has three fields:

1. PM : The first field is the link to the PlanetMath article, along with the article's object ID.
2. WP : The second field is either a "guessed" link to a correspondingly named Wikipedia article, produced by the script which generated the list, or one or more manually entered links to the corresponding Wikipedia articles on the subject.
3. Status : The third field is the status field, which explains the current status of the entry. The recommended status entries are:

Status	means PM article
N	not needed
A	adequately covered
C	copied
M	merged
NC	needs copying
NM	needs merging

• Please update the WP and Status fields as appropriate.
• if the WP field is correct please remove the qualifier "guess".
• If the corresponding Wikipedia article exists, but the link to it is wrong, please fix the link.
• If you copy or merge an article from PlanetMath, please update the WP and Status fields for that entry.
• If you have any comments, for example, thoughts on how the PlanetMath article compares to the corresponding Wikipedia article(s), please place such comments on a new indented line following the entry. Comments of this kind are very valuable.

Don't forget to include the relevant template if you copy over text or feel like an external link is warranted

• {{planetmath|id=|title=}} for copied over text
• {{planetmath reference|id=|title=}} for an external link

See the main page for examples and usage criteria.

One can use the web-based program Pmform to convert PlanetMath articles to the Wikipedia format. As a side benefit, this tool will place the PlanetMath template for you.

52-00 General reference works (handbooks, dictionaries, bibliographies, etc.)

• PM: convex analysis, id=6954 -- WP guess: convex analysis -- Status:

52A01 Axiomatic and generalized convexity

• PM: convex combination, id=401 -- WP: convex combination -- Status: A

Or one might want to copy some formulae, in addition to a verbal description. Mikkalai 02:47, 14 Feb 2005 (UTC)

52A07 Convex sets in topological vector spaces

• PM: Fréchet space, id=3528 -- WP: Fréchet space -- Status: A

Unless someone wants to add proofs (which is IMO not really necessary in encyclopedia) Mikkalai 02:50, 14 Feb 2005 (UTC)

• PM: recession cone, id=8471^new! -- WP guess: recession cone -- Status:

52A20 Convex sets in $n$ dimensions (including convex hypersurfaces)

• PM: Carathéodory's theorem, id=4730 -- WP: Carathéodory's theorem (convex hull) -- Status: A

Mikkalai 03:38, 14 Feb 2005 (UTC)

• PM: proper cone, id=6199 -- WP : proper cone -- Status: M

Merged into Cone (geometry), and proper cone redirects thereMikkalai 03:38, 14 Feb 2005 (UTC)

Renamed cone (geometry) to cone (linear algebra). Jorge Stolfi 03:26, 23 December 2005 (UTC)

• PM: Radon's lemma, id=4710 -- WP : Radon's lemma -- Status: C

Jtwdog 21:16, 28 October 2005 (UTC)

52A21 Finite-dimensional Banach spaces (including special norms, zonoids, etc.)

• PM: Wulff Theorem, id=7144 -- WP guess: Wulff Theorem -- Status:

52A35 Helly-type theorems and geometric transversal theory

• PM: Helly's theorem, id=4728 -- WP: Helly's theorem -- Status: A

Note: PM proof is much shorter, whatever this may mean. User:Mikkalai 15:30, 3 February 2005 (UTC)

52A99 Miscellaneous

• PM: convex set, id=243 -- WP : convex set -- Status: A

Mikkalai 03:51, 14 Feb 2005 (UTC)

• PM: extreme point, id=5920 -- WP : extreme point -- Status: A

Mikkalai 03:51, 14 Feb 2005 (UTC)

• PM: if A is convex and f linear then f(A) and f^{-1}(A) are convex, id=6175 -- WP guess: if A is convex and f linear then f(A) and f^-1(A) are convex -- Status: N

Nameless proposition. Mikkalai 03:51, 14 Feb 2005 (UTC)

• PM: internal point, id=5923 -- WP : internal point -- Status: NC

Mikkalai 03:51, 14 Feb 2005 (UTC)

• PM: extreme subset of convex set, id=7252 -- WP guess: extreme subset of convex set -- Status:

• PM: proof of properties of extreme subsets of a closed convex set, id=7264 -- WP guess: proof of properties of extreme subsets of a closed convex set -- Status:

• PM: properties of extreme subsets of a closed convex set, id=7253 -- WP guess: properties of extreme subsets of a closed convex set -- Status:

• PM: face of a convex set, id=8530^new! -- WP guess: face of a convex set -- Status:

• PM: alternative definition of face of a convex set, id=9320^new! -- WP guess: alternative definition of face of a convex set -- Status:

52B05 Combinatorial properties (number of faces, shortest paths, etc.)

• PM: embedding, id=7385 -- WP guess: embedding -- Status:

52B11 $n$-dimensional polytopes

• PM: isothetic, id=7912^new! -- WP guess: isothetic -- Status:

52B40 Matroids (realizations in the context of convex polytopes, convexity in combinatorial structures, etc.)

• PM: polytope, id=5544 -- WP: Convex polytope -- Status: NM

Jtwdog 21:21, 28 October 2005 (UTC)

• PM: f-vector, id=9264^new! -- WP guess: f-vector -- Status:

• PM: Weyl-Minkowski theorem, id=9262^new! -- WP guess: Weyl-Minkowski theorem -- Status:

52B99 Miscellaneous

• PM: pure simplicial complex, id=5780 -- WP: pure simplicial complex -- Status: A

Redirect to simplicial complex Mikkalai 00:19, 11 Feb 2005 (UTC)

• PM: hyperplane arrangement, id=7760^new! -- WP guess: hyperplane arrangement -- Status:

• PM: intersection semilattice of a subspace arrangement, id=7761^new! -- WP guess: intersection semilattice of a subspace arrangement -- Status:

• PM: zonotope, id=7749^new! -- WP guess: zonotope -- Status:

52C35 Arrangements of points, flats, hyperplanes

• PM: K-distance set, id=5788 -- WP : K-distance set -- Status: NC

Mikkalai 05:12, 14 Feb 2005 (UTC)