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Rotation matrix 
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#1
Mar3012, 03:57 AM

#2
Mar3012, 06:29 AM

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Rotation about the xaxis through angle [itex]\alpha[/itex] is given by the matrix
[tex]\begin{bmatrix}1 & 0 & 0 \\ 0 & cos(\alpha) & sin(\alpha) \\ 0 & sin(\alpha) & cos(\alpha)\end{bmatrix}[/tex] Rotation about the yaxis through angle [itex]\beta[/itex] is given by the matrix [tex]\begin{bmatrix}cos(\beta) & 0 & sin(\beta) \\ 0 & 1 & 0 \\ sin(\beta) & 0 & cos(\beta)\end{bmatrix}[/tex] Rotation about the zaxis through angle [itex]\gamma[/itex] is given by the matrix [tex]\begin{bmatrix} cos(\gamma) & sin(\gamma) & 0 \\ sin(\gamma) & cos(\gamma) & 0 \\ 0 & 0 & 1\end{bmatrix}[/tex] The result of all those rotations is the product of those matrices. Be sure to multiply in the correct order. 


#3
Mar3012, 09:49 AM

P: 686

I suspect that there's a minus sign somewhere wrongly placed in your matrices Halls, am I correct? I moved the minus sign in your second matrix to the lower sine but there's still something wrong for this is my result:



#4
Mar3012, 10:23 AM

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Rotation matrix
No, all of the minus signs are correctly placed. I am, of course, assuming that a positive angle gives a rotation "counterclockwise" looking at the plane from "above" from the positive axis of rotation.



#5
Mar3012, 10:36 AM

P: 686

But the wiki page shows a different position for the minus sign of your second matrix:
http://en.wikipedia.org/wiki/Rotation_matrix. 


#6
Mar3012, 12:56 PM

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