The dihedral groups contain only proper rotations, no reflections or inversions. D4 has 8 elements. It has the 4-element subgroup C4 of rotations about the z-axis, and four 180-degree rotations about axes that lie in the xy-plane and are separated by 45 degrees. --- Ray Tayek <rtayek@attbi.com> wrote:
hi, iirc, the elements are : e, r, r2, r3, h, v, d1, and d2.
does h flip about the x or y axis?
is d1 / or \?
or are there a more mnemonic set of element names?
thanks
--- ray tayek http://tayek.com/ actively seeking mentoring or telecommuting work vice chair orange county java users group http://www.ocjug.org/ hate spam? http://samspade.org/ssw/
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