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Topic: Reposition 3D plane slice
Replies: 16   Last Post: Jun 15, 2012 5:22 PM

 Messages: [ Previous | Next ]
 Myles Posts: 11 Registered: 6/14/12
Reposition 3D plane slice
Posted: Jun 14, 2012 5:40 PM

"Matt J" wrote in message <jrdk1a\$6tr\$1@newscl01ah.mathworks.com>...
> "Myles" wrote in message <jrdhgm\$on6\$1@newscl01ah.mathworks.com>...
> >
> > Sorry, I guess I wasn't specific enough - I have three separate groups of points (all of which still lie in the same plane originally), after the transformation two are lying in the same plane and one is lying a long distance away. However, none of them are parallel to the xy axis. I've uploaded a few pictures so you can see better what I'm trying to say.
> >
> > http://s177.photobucket.com/albums/w227/MilesMaybe/MATLAB%20images/

> ============
>
> The figures are unlabeled, and so a bit hard to interpret.
> In any case, can you do this for me? Tell me what the value of Ztilt is. Also, apply the transformation to Ztilt (as if it were one of your 3D points) and tell me the result.

Yeah, I realized that almost immediately after I posted - I should have shown you views from xy, xz, yz, etc. I just mostly wanted you to see how the plane was originally oriented in all directions and the points general range of:
X : (0 to 30)
Y : (10 to 50)
Z : (16 to 28)

So anyways,

Ztilt = [0.1682 0.3477 -0.9224] <--- this is normalized of [16.7243, 34.5791,-91.7416]
u = cross(Ztilt, [0 0 1])
u = [0.3477 - 0.1682 0]
NewPoint = AxelRot(Ztilt', deg, u, [0 0 0])
NewPoint = [0.3102; 0.6414; -0.7017]

Sorry if I'm slow or missing something basic - still relatively new to MATLAB, and Linear Algebra was never my strong point. But I do really appreciate the help.

Date Subject Author
6/14/12 Myles
6/14/12 Matt J
6/14/12 Matt J
6/14/12 Myles
6/14/12 Matt J
6/14/12 Myles
6/14/12 Matt J
6/14/12 Myles
6/14/12 Matt J
6/14/12 Myles
6/15/12 Matt J
6/15/12 Matt J
6/15/12 Myles
6/15/12 Matt J
6/15/12 Myles
6/15/12 Matt J
6/14/12 Myles