Difference between revisions of "Talk:Quaternion"
(Oops) |
m (typos) |
||
| Line 3: | Line 3: | ||
Q' = zQz<sup>-1</sup> | Q' = zQz<sup>-1</sup> | ||
but LSL proceeds in reverse order | but LSL proceeds in reverse order when it rotates a vector by a rotation (* operator) : | ||
Q' = z<sup>-1</sup>Qz | Q' = z<sup>-1</sup>Qz | ||
| Line 10: | Line 10: | ||
for direction of positive rotations. | for direction of positive rotations. | ||
This has | This has consequences over the rest of computations. | ||
-- Catherine Pfeffer, 2007-12-06 | -- Catherine Pfeffer, 2007-12-06 | ||
Revision as of 07:19, 7 December 2007
This text says that you rotate a vector Q by a rotation z with the formula :
Q' = zQz-1
but LSL proceeds in reverse order when it rotates a vector by a rotation (* operator) :
Q' = z-1Qz
Just give a try if you don't believe me... ;-). The reason is LSL follows the right-hand rule for direction of positive rotations.
This has consequences over the rest of computations.
-- Catherine Pfeffer, 2007-12-06
This text has two shemas at the end. If you look well at it, the 90° rotation in the first schema and
in the second schema are supposed to be opposite (once in z direction, the other time in -z direction)
but the pink arrow materializing the rotation is the same.
It's the first schema that is correct (LSL follows right-hand rule for direction of positive rotations)
-- Catherine Pfeffer, 2007-12-07