Cartesian coordinates Dodecahedron
the coordinates of 8 vertices of original cube are:
(±1, ±1, ±1)
the coordinates of 12 vertices of cross-edges are:
(0, ±(1 + h), ±(1 − h))
(±(1 + h), ±(1 − h), 0)
(±(1 − h), 0, ±(1 + h))
where h height of wedge-shaped roof above faces of cube. when h = 1, 6 cross-edges degenerate points , rhombic dodecahedron formed. when h = 0, cross-edges absorbed in facets of cube, , pyritohedron reduces cube. when h = √5 − 1/2, inverse of golden ratio, result regular dodecahedron.
pyritohedra in dual positions
a reflected pyritohedron made swapping nonzero coordinates above. 2 pyritohedra can superimposed give compound of 2 dodecahedra seen in image here.
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