Heptagonal-enneagonal duoprismatic prism

The heptagonal-enneagonal duoprismatic prism or heep, also known as the heptagonal-enneagonal prismatic duoprism, is a convex uniform duoprism that consists of 2 heptagonal-enneagonal duoprisms, 7 square-enneagonal duoprisms and 9 square-heptagonal duoprisms. Each vertex joins 2 square-heptagonal duoprisms, 2 square-enneagonal duoprisms, and 1 heptagonal-enneagonal duoprism. Being a prism based on an orbiform polytope, it is also a convex segmentoteron.

Vertex coordinates
The vertices of a heptagonal-enneagonal duoprismatic prism of edge length 4sin(π/7)sin(π/9) are given by: where j = 2, 4, 6 and k = 2, 4, 8.
 * $$\left(2\sin\frac\pi9,\,0,\,2\sin\frac\pi7,\,0,\,±2\sin\frac\pi7\sin\frac\pi9\right),$$
 * $$\left(2\sin\frac\pi9,\,0,\,2\cos\left(\frac{k\pi}9\right)\sin\frac\pi7,\,±2\sin\left(\frac{k\pi}9\right)\sin\frac\pi7,\,±2\sin\frac\pi7\sin\frac\pi9\right),$$
 * $$\left(2\sin\frac\pi9,\,0,\,-\sin\frac\pi7,\,±\sqrt3\sin\frac\pi7,\,±2\sin\frac\pi7\sin\frac\pi9\right),$$
 * $$\left(2\cos\left(\frac{j\pi}7\right)\sin\frac\pi9,\,±2\sin\left(\frac{j\pi}7\right)\sin\frac\pi9,\,2\sin\frac\pi7,\,0,\,±2\sin\frac\pi7\sin\frac\pi9\right),$$
 * $$\left(2\cos\left(\frac{j\pi}7\right)\sin\frac\pi9,\,±2\sin\left(\frac{j\pi}7\right)\sin\frac\pi9,\,2\cos\left(\frac{k\pi}9\right)\sin\frac\pi7,\,±2\sin\left(\frac{k\pi}9\right)\sin\frac\pi7,\,±2\sin\frac\pi7\sin\frac\pi9\right),$$
 * $$\left(2\cos\left(\frac{j\pi}7\right)\sin\frac\pi9,\,±2\sin\left(\frac{j\pi}7\right)\sin\frac\pi9,\,-\sin\frac\pi7,\,±\sqrt3\sin\frac\pi7,\,±2\sin\frac\pi7\sin\frac\pi9\right),$$

Representations
A heptagonal-enneagonal duoprismatic prism has the following Coxeter diagrams:
 * x x7o x9o (full symmetry)
 * xx7oo xx9oo&#x (heptagonal-enneagonal duoprism atop heptagonal-enneagonal duoprism)