Enneagonal duoprismatic prism

The enneagonal duoprismatic prism or eep, also known as the enneagonal-enneagonal prismatic duoprism, is a convex uniform duoprism that consists of 2 enneagonal duoprisms and 18 square-enneagonal duoprisms. Each vertex joins 4 square-enneagonal duoprisms and 1 enneagonal duoprism. Being a prism based on an orbiform polytope, it is also a convex segmentoteron.

Vertex coordinates
The vertices of an enneagonal duoprismatic prism of edge length 2sin(π/9) are given by: where j, k = 2, 4, 8.
 * $$\left(1,\,0,\,1,\,0,\,±\sin\frac\pi9\right),$$
 * $$\left(1,\,0,\,\cos\frac{k\pi}9,\,±\sin\frac{k\pi}9,\,±\sin\frac\pi9\right),$$
 * $$\left(1,\,0,\,-\frac12,\,±\frac{\sqrt3}2,\,±\sin\frac\pi9\right),$$
 * $$\left(\cos\frac{j\pi}9,\,±\sin\frac{j\pi}9,\,1,\,0,\,±\sin\frac\pi9\right),$$
 * $$\left(\cos\frac{j\pi}9,\,±\sin\frac{j\pi}9,\,\cos\frac{k\pi}9,\,±\sin\frac{k\pi}9,\,±\sin\frac\pi9\right),$$
 * $$\left(\cos\frac{j\pi}9,\,±\sin\frac{j\pi}9,\,-\frac12,\,±\frac{\sqrt3}2,\,±\sin\frac\pi9\right),$$
 * $$\left(-\frac12,\,±\frac{\sqrt3}2,\,1,\,0,\,±\sin\frac\pi9\right),$$
 * $$\left(-\frac12,\,±\frac{\sqrt3}2,\,\cos\frac{k\pi}9,\,±\sin\frac{k\pi}9,\,±\sin\frac\pi9\right),$$
 * $$\left(-\frac12,\,±\frac{\sqrt3}2,\,-\frac12,\,±\frac{\sqrt3}2,\,±\sin\frac\pi9\right),$$

Representations
An enneagonal duoprismatic prism has the following Coxeter diagrams:
 * x x9o x9o (full symmetry)
 * xx9oo xx9oo&#x (enneagonal duoprism atop enneagonal duoprism)