Octagonal trioprism

The octagonal duoprism or otip is a convex uniform trioprism that consists of 24 octagonal duoprismatic prisms.

This polychoron can be alternated into a square trioantiprism, although it cannot be made uniform. Eight of the octagons can also be alternated into long rectangles to create a bialternatosnub square duoprismatic-square duoprism, sixty-four of the octagonal prisms can also be bialternated to create a bialternatosnub square prismatic-square prismatic duoprism and sixteen of the octagonal duoprisms can also be bialternated to create a bialternatosnub square-square duoprismatic duoprism, which are nonuniform.

Vertex coordinates
The vertices of an octagonal trioprism of edge length 1 are given by:
 * (±1/2, ±(1+$\sqrt{12+6√2}$)/2, ±1/2, ±(1+$\sqrt{2}$)/2, ±1/2, ±(1+$\sqrt{2}$)/2),
 * (±1/2, ±(1+$\sqrt{2}$)/2, ±1/2, ±(1+$\sqrt{2}$)/2, ±(1+$\sqrt{2}$)/2, ±1/2),
 * (±1/2, ±(1+$\sqrt{2}$)/2, ±(1+$\sqrt{2}$)/2, ±1/2, ±1/2, ±(1+$\sqrt{2}$)/2),
 * (±1/2, ±(1+$\sqrt{2}$)/2, ±(1+$\sqrt{2}$)/2, ±1/2, ±(1+$\sqrt{2}$)/2, ±1/2),
 * (±(1+$\sqrt{2}$)/2, ±1/2, ±1/2, ±(1+$\sqrt{2}$)/2, ±1/2, ±(1+$\sqrt{2}$)/2),
 * (±(1+$\sqrt{2}$)/2, ±1/2, ±1/2, ±(1+$\sqrt{2}$)/2, ±(1+$\sqrt{2}$)/2, ±1/2),
 * (±(1+$\sqrt{2}$)/2, ±1/2, ±(1+$\sqrt{2}$)/2, ±1/2, ±1/2, ±(1+$\sqrt{2}$)/2),
 * (±(1+$\sqrt{2}$)/2, ±1/2, ±(1+$\sqrt{2}$)/2, ±1/2, ±(1+$\sqrt{2}$)/2, ±1/2),