Enneagonal-decagonal duoprism

The enneagonal-decagonal duoprism or edidip, also known as the 9-10 duoprism, is a uniform duoprism that consists of 9 decagonal prisms and 10 enneagonal prisms, with two of each joining at each vertex.

Vertex coordinates
The coordinates of an enneagonal-decagonal duoprism, centered at the origin and with edge length 2sin(π/9), are given by:
 * (1, 0, ±sin(π/9), ±sin(π/9)$\sqrt{(5+√5)/2}$),
 * (1, 0, ±sin(π/9)(3+$\sqrt{2}$)/2, ±sin(π/9)$\sqrt{5+2√5}$),
 * (1, 0, ±sin(π/9)(1+$\sqrt{5}$), 0),
 * (cos(2π/9), ±sin(2π/9), ±sin(π/9), ±sin(π/9)$\sqrt{(5+√5)/2}$),
 * (cos(2π/9), ±sin(2π/9), ±sin(π/9)(3+$\sqrt{5}$)/2, ±sin(π/9)$\sqrt{5+2√5}$),
 * (cos(2π/9), ±sin(2π/9), ±sin(π/9)(1+$\sqrt{5}$), 0),
 * (cos(4π/9), ±sin(4π/9), ±sin(π/9), ±sin(π/9)$\sqrt{(5+√5)/2}$),
 * (cos(4π/9), ±sin(4π/9), ±sin(π/9)(3+$\sqrt{5}$)/2, ±sin(π/9)$\sqrt{5+2√5}$),
 * (cos(4π/9), ±sin(4π/9), ±sin(π/9)(1+$\sqrt{5}$), 0),
 * (–1/2, ±$\sqrt{(5+√5)/2}$/2, ±sin(π/9), ±sin(π/9)$\sqrt{5}$),
 * (–1/2, ±$\sqrt{3}$/2, ±sin(π/9)(3+$\sqrt{5+2√5}$)/2, ±sin(π/9)$\sqrt{3}$),
 * (–1/2, ±$\sqrt{5}$/2, ±sin(π/9)(1+$\sqrt{(5+√5)/2}$), 0),
 * (cos(8π/9), ±sin(8π/9), ±sin(π/9), ±sin(π/9)$\sqrt{3}$),
 * (cos(8π/9), ±sin(8π/9), ±sin(π/9)(3+$\sqrt{5}$)/2, ±sin(π/9)$\sqrt{5+2√5}$),
 * (cos(8π/9), ±sin(8π/9), ±sin(π/9)(1+$\sqrt{5}$), 0).

Representations
An enneagonal-decagonal duoprism has the following Coxeter diagrams:


 * x9o x10o (full symmetry)
 * x5x x9o (decagons as dipentagons)