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Pedagoguery Software Releases Poly
Monday,December 13, 1999
Press Release Edited By Applelinks Contributing Editor Charles W. Moore
Poly is a shareware program for exploring and constructing polyhedra. With Poly,
you can manipulate polyhedral solids on the computer in a variety of ways. Flattened
versions (nets) of polyhedra may be printed and then cut out, folded, and taped, to
produce three-dimensional models. Unregistered copies are fully-functional, but
Pedagoguery asks users to remember that Poly is for evaluation purposes only until
you have registered.
Poly offers an English, a Spanish, a French, and a Korean interface.
Poly System Requirements:
680x0 Macintosh 68000 - 68040 System 6 - MacOS 8.1
Power Macintosh Any PowerMac System 7.1.2 - MacOS 9.0
(Windows versions also available)
Poly includes all of the following polyhedra:
Platonic Solids
Each platonic polyhedron is constructed using (multiple copies of) a single regular
polygon; the same number of polygonal faces is used around each vertex. A polygon
is regular if all of its edges have the same length and all of its interior angles are
equal. Both the equilateral triangle and square are regular polygons.
Archimedean Solids
The Archimedean solids were defined historically by Archimedes, although we have
lost his writings. All of the Archimedean solids are uniform polyhedra with regular
faces. A polyhedron with regular polygonal faces is uniform if there are symmetry
operations that take one vertex through all of the other vertices and no other
points in space. For example, the cube has rotation by 90° around an axis and
reflection through a plane perpendicular to that axis as its symmetry operations. A
common heuristic for the Archimedean solids is that the arrangement of faces
surrounding each vertex must be the same for all vertices. Although all of the
Archimedean solids have this property, so does the elongated square gyrobicupola
(Johnson solid which is not an Archimedean solid.
Prisms and Anti-Prisms
After the Platonic and Archimedean solids, the only remaining convex uniform
polyhedra with regular faces are prisms and anti-prisms. This was shown by
Johannes Kepler, who also gave the names commonly used for the Archimedean
solids.
Johnson Solids
After taking into account the preceeding three categories, there are only a finite
number of convex polyhedra with regular faces left. The enumeration of these
polyhedra was performed by Norman W. Johnson.
Catalan Solids
The Catalan solids are duals of Archimedean solids. A dual of a polyhedron is
constructed by replacing each face with a vertex, and each vertex with a face. For
example, the dual of the icosahedron is the dodecahedron; the dual of the
dodecahedron is the icosahedron.
Dipyramids and Deltohedrons
Dipyramids are duals of prisms; deltohedrons are duals of anti-prisms.
For more information, visit:
http://www.peda.com/poly/
Dipyramids are duals of prisms; deltohedrons are duals of anti-prisms.
Charles W. Moore
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