Square antiprism (EntityTopic, 13)

From Hi.gher. Space

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== Geometry ==
== Geometry ==
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* The [[planar]] [[cross-section]]s of a square antiprism in the [!z] plane are ir[[regular]] [[octagon]]s.
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* The [[planar]] [[cross-section]]s of a square antiprism in the [!z] plane are [[octagon]]s, giving a regular octagon in the middle and degenerating to squares at the ends.
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* The planar cross-sections of a square antiprism in the [!x] and [!y] planes are [[trapezium]]s.
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* The planar cross-sections of a square antiprism in the [!x] and [!y] planes are irregular [[pentagon]]s, degenerating to [[trapezium]]s in the middle and at the ends.
{{Polyhedra}}
{{Polyhedra}}
[[Category:Trishapes]]
[[Category:Trishapes]]

Revision as of 10:47, 5 December 2010


The square antiprism is a special case of an antiprism where the base is a square.

Geometry

  • The planar cross-sections of a square antiprism in the [!z] plane are octagons, giving a regular octagon in the middle and degenerating to squares at the ends.
  • The planar cross-sections of a square antiprism in the [!x] and [!y] planes are irregular pentagons, degenerating to trapeziums in the middle and at the ends.


Notable Trishapes
Regular: tetrahedroncubeoctahedrondodecahedronicosahedron
Direct truncates: tetrahedral truncatecubic truncateoctahedral truncatedodecahedral truncateicosahedral truncate
Mesotruncates: stauromesohedronstauroperihedronstauropantohedronrhodomesohedronrhodoperihedronrhodopantohedron
Snubs: snub staurohedronsnub rhodohedron
Curved: spheretoruscylinderconefrustumcrind