Duoprism

A duoprism is a class of polytopes formed as the Cartesian product of two polytopes. The simplest non-trivial duoprism is the 3-3 duoprism, which is the Cartesian product of two triangles. The dual of a duoprism is a duopyramid. The duoprism is the second in an infinite series of multiprisms, which include prisms, trioprisms and tetraprisms. The hypercubes are duoprisms made from lower-dimensional hypercubes.

If one of the polytopes is a point, then the resulting polytope is identical to the other polytope. If one of the polytopes is a line segment, then the resulting polytope is the prism of the other polytope. Neither of these cases are usually considered duoprisms.

The vertex coordinates of a duoprism is determined by all ordered pairs of the two polytopes a and b. As such, they have a number of vertices equal to the product of the number of vertices of each polytope.