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== Filling ==
== Filling ==
There is some controversy on how to colour the faces of this polyhedron. Although the common way to fill in a polygon is to just colour its whole interior, the middle of the pentagrams are over empty space, as can be seen from the picture of the [[great dodecahemicosahedron]] above. Hence, some, such as Jonathan Bowers, do not fill in the middle of the pentagram: this filling has been called "neo filling". In the neo filling, orientable polyhedra are filled traditionally, but non-orientable polyhedra have their faces filled with the modulo-2 method (only odd-[[density (polytope)|density]] regions are filled in).<ref name="bowers">http://polytope.net/hedrondude/polychora.htm</ref>
There is some controversy on how to colour the faces of this polyhedron. Although the common way to fill in a polygon is to just colour its whole interior, the middle of the pentagrams are over empty space, as can be seen from the picture of the [[great dodecahemicosahedron]] above. Hence, some, such as Jonathan Bowers, do not fill in the middle of the pentagram: this filling has been called "natural filling". In the natural filling, orientable polyhedra are filled traditionally, but non-orientable polyhedra have their faces filled with the modulo-2 method (only odd-[[density (polytope)|density]] regions are filled in).<ref name="bowers">http://polytope.net/hedrondude/polychora.htm</ref>


{| class="wikitable" width="400" style="vertical-align:top;text-align:center"
{| class="wikitable" width="400" style="vertical-align:top;text-align:center"
|align=center|[[Image:Small dodecahemicosahedron.png|150px]]<BR>Traditional filling
|align=center|[[Image:Small dodecahemicosahedron.png|150px]]<BR>Traditional filling
|align=center|[[Image:Small dodecahemicosahedron 2.png|150px]]<BR>"Neo filling"
|align=center|[[Image:Small dodecahemicosahedron 2.png|150px]]<BR>"Natural/Neo filling"
|}
|}



Revision as of 23:12, 3 November 2017

Small dodecahemicosahedron
Type Uniform star polyhedron
Elements F = 22, E = 60
V = 30 (χ = −8)
Faces by sides 12{5/2}+10{6}
Coxeter diagram
Wythoff symbol 5/3 5/2 | 3 (double covering)
Symmetry group Ih, [5,3], *532
Index references U62, C78, W100
Dual polyhedron Small dodecahemicosacron
Vertex figure
6.5/2.6.5/3
Bowers acronym Sidhei

In geometry, the small dodecahemicosahedron is a nonconvex uniform polyhedron, indexed as U62. Its vertex figure is a crossed quadrilateral.

It is a hemipolyhedron with ten hexagonal faces passing through the model center.

Its convex hull is the icosidodecahedron. It also shares its edge arrangement with the dodecadodecahedron (having the pentagrammic faces in common), and with the great dodecahemicosahedron (having the hexagonal faces in common).


Dodecadodecahedron

Small dodecahemicosahedron

Great dodecahemicosahedron

Icosidodecahedron (convex hull)

Filling

There is some controversy on how to colour the faces of this polyhedron. Although the common way to fill in a polygon is to just colour its whole interior, the middle of the pentagrams are over empty space, as can be seen from the picture of the great dodecahemicosahedron above. Hence, some, such as Jonathan Bowers, do not fill in the middle of the pentagram: this filling has been called "natural filling". In the natural filling, orientable polyhedra are filled traditionally, but non-orientable polyhedra have their faces filled with the modulo-2 method (only odd-density regions are filled in).[1]


Traditional filling

"Natural/Neo filling"

References

See also

  • Weisstein, Eric W. "Small dodecahemicosahedron". MathWorld.
  • Uniform polyhedra and duals