Re: Solve & RotationMatrix
- To: mathgroup at smc.vnet.net
- Subject: [mg76031] Re: Solve & RotationMatrix
- From: CKWong <CKWong.P at gmail.com>
- Date: Tue, 15 May 2007 04:49:30 -0400 (EDT)
- References: <f21g0q$7d6$1@smc.vnet.net><f23qq6$oa3$1@smc.vnet.net>
I could be wrong but as I see it, the only thing that kept your algorithm from working is that there is no Mathematica function called RotationMatrix. If you replace the line RotX = RotationMatrix[\[Alpha], VectX]; with RotX={ {Cos[\[Alpha]],-Sin[\[Alpha]],0}, {Sin[\[Alpha]],Cos[\[Alpha]], 0}, {0,0,1} }; and similarly for RotY and RotZ, everything should be fine. On May 14, 5:51 pm, Mathieu G <ellocoma... at free.fr> wrote: > CKWon... at gmail.com a =E9crit :> Obviously, you need to provide the function RotationMatrix[ angle, > > axisVector ] for the algorithm to work. > > > On the other hand, matrices for rotations about the Cartesian axes, > > i.e., RotX,RotY, & RotZ, can be written done directly. Why not do so? > > Hi, > Thank you for your reply. > I am not interested in a simple rotation matrix around an axis, but in > finding the angles corresponding to a 3D rotation matrix. > I compute VectN which is the vector normal to my surface, and I am > interested in getting the rotation parameters that bring VectY to VectN. > Regards, > Mathieu