# Compound of two digons

(Redirected from Compound of 2 digons)

Compound of two digons | |
---|---|

Rank | 2 |

Type | Regular |

Notation | |

Schläfli symbol | {4/2} |

Elements | |

Components | 2 digons |

Edges | 4 |

Vertices | 4 |

Vertex figure | Dyad, length 0 |

Measures (edge length 1) | |

Circumradius | |

Area | 0 |

Angle | 0° |

Central density | 2 |

Related polytopes | |

Army | Square, edge length |

Dual | Compound of two digons |

Conjugate | None |

Abstract & topological properties | |

Orientable | Yes |

Properties | |

Symmetry | B_{2}, order 8 |

Convex | No |

Nature | Tame |

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: