Heptagonal-heptagrammic duoprism

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

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

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