Compound of two digons

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Compound of two digons
Rank2
TypeRegular
Notation
Schläfli symbol{4/2}
Elements
Components2 digons
Edges4
Vertices4
Vertex figureDyad, length 0
Measures (edge length 1)
Circumradius
Area0
Angle
Central density2
Related polytopes
ArmySquare, edge length
DualCompound of two digons
ConjugateNone
Abstract & topological properties
OrientableYes
Properties
SymmetryB2, order 8
ConvexNo
NatureTame
An embedding of the compound of two digons on the surface of a 2-sphere. Note its vertices are not placed at the intersection of its edges.

The stellated square, also called the compound of two digons, is a regular polygon compound, being the compound of two digons. As such it has 4 edges and 4 vertices. It is degenerate if embedded in Euclidean space, as its edges coincide. However it has a non-degenerate embeddeding on the surface of a 2-sphere.

It can be formed as a degenerate stellation of the square, by extending the edges to infinity.

Its quotient prismatic equivalent is the tetrahedron, which is three-dimensional.

Vertex coordinates[edit | edit source]

Coordinates for the vertices of a compound of two digons of edge length 1 centered at the origin are given by: