From: "YILMAZ " <>
Newsgroups: comp.soft-sys.matlab
Subject: Re: Rotate 3D object to align with x-y plane
Date: Fri, 2 Jul 2010 07:42:06 +0000 (UTC)
Organization: Istanbul Bilgi Universitesi
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"Roger Stafford" <> wrote in message <ht1pm2$1v$>...
> "Marcin " <> wrote in message <hsvvv6$7rl$>...
> > Hi,
> > 
> > I have a set of points describing a 3D object, which has been rotated by some small angle (below 45 degrees) with respect to x,y and z axis. I want to rotate it back to align it with the x-y plane, but the problem is I don't know the angles, so I need to calculate/estimate them somehow. So the questions are:
> > 
> > 1. how to plot the object in a mesh like manner?
> > 2. how to calculate the angles?
> > 3. how to rotate it when I know the angles?
> > 
> > Many thanks
>   I am not clear about what you mean when you say, "I want to rotate it back to align it with the x-y plane."  Do the set of points "describing" the 3D object all lie in a plane?  If so, there are many ways to rotate them so they all come to lie in the x-y plane.  Any rotation axis which lies in the plane which bisects the dihedral angle between the points' plane and the x-y plane could be used.  You can achieve any orientation you wish for the resulting x-y plane points.  If you have a preferred final orientation for the points as they lie in the x-y plane, then I could give you a specific method for solving your problem.  As it stands, the problem appears to be indeterminate if I have understood you correctly.
> Roger Stafford

Hi Roger;
I have a some problem with rotating my matrices. My matrices describes a rectangle. 4x10 data set. I want this rectangle to move with 30 degree angel. 

For example in ms office word we create a new rectangle. After that we can rotate it 30 ° angle. 

I tried to use different rules that I thinked, but I could not achieve. Can you offer me a rule? 
Thanks for your help