Dear all,
In Human Brain Function 2nd ed.
(http://www.fil.ion.ucl.ac.uk/spm/doc/books/hbf2/pdfs/Ch2.pdf) Chapter 2
section 1 about rigid body registration page 7, it is written that in
2D, a rotation by theta radians around the origin is given by:
y1 = cos(theta)x1 + sin(theta)x2
y2 = -sin(theta)x1 + cos(theta)x2
But isn't it supposed to be
y1 = cos(theta)x1 - sin(theta)x2
y2 = sin(theta)x1 + cos(theta)x2
I thought it might be a typo but the first formula is the one actually
implemented. Can you explain me?
Regards,
Remi.
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