This was so obvious in retrospect, although I'm battling the corner cases (and the sign of T) now. Thanks! Robert On Saturday, June 7, 2014, Dan Asimov <dasimov@earthlink.net> wrote:
In almost all cases, V := (A-A')x(B-B') will be a vector in the direction of the axis of rotation. Knowing V makes it easy to project say A and A' onto the perpendicular plane to C to determine the angle T.
The remaining cases should be easy to exclude or deal with.
--Dan
On Jun 7, 2014, at 1:32 AM, Robert Smith <quad@symbo1ics.com <javascript:;>> wrote:
Let A and B be unit vectors in R^3. Suppose they are rotated about some vector V by an angle T, resulting in A' and B' respectively. What are V and T?
I set up a quadratic system using quaternions and got a result that was 3 million terms large. Am I missing something?
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