Heptagrammic-octagonal duoprism

The heptagrammic-octagonal duoprism, also known as sheodip or the 7/2-8 duoprism, is a uniform duoprism that consists of 8 heptagrammic prisms and 7 octagonal prisms, with 2 of each at each vertex.

The name can also refer to the great heptagrammic-octagonal duoprism.

Vertex coordinates
The coordinates of a heptagrammic-octagonal duoprism, centered at the origin and with edge length 2sin(2π/7), are given by: where j = 2, 4, 6.
 * $$\left(1,\,0,\,±\sin\frac{2\pi}7,\,±\left(1+\sqrt2\right)\sin\frac{2\pi}7\right),$$
 * $$\left(1,\,0,\,±\left(1+\sqrt2\right)\sin\frac{2\pi}7,\,±\sin\frac{2\pi}7\right),$$
 * $$\left(\cos\left(\frac{j\pi}7\right),\,±\sin\left(\frac{j\pi}7\right),\,±\sin\frac{2\pi}7,\,±\left(1+\sqrt2\right)\sin\frac{2\pi}7\right),$$
 * $$\left(\cos\left(\frac{j\pi}7\right),\,±\sin\left(\frac{j\pi}7\right),\,±\left(1+\sqrt2\right)\sin\frac{2\pi}7,\,±\sin\frac{2\pi}7\right),$$

Representations
A heptagrammic-octagonal duoprism has the following Coxeter diagrams:
 * x7/2o x8o (full symmetry)
 * x4x x7/2o (BC2×I2(7) symmetry, octagons as ditetragons)