How Does Quaternion Rotation Affect Another Quaternion?

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Quaternion rotation can be applied to both vectors and quaternions using the formula qvq*, where "q" is the rotation quaternion and "v" is the entity being rotated. When "v" is a quaternion, the result is a combination of the scalar part remaining unchanged while the vector part is rotated as per the quaternion's properties. This highlights that the operation effectively rotates the vector component of the quaternion while preserving its scalar component. The discussion also touches on the mathematical understanding of quaternions and their application in 3D programming or math classes. Overall, the conversation clarifies how quaternion rotation operates differently when applied to quaternions versus traditional vectors.
Plott029
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If we take a vector "v" and utilize a quaternion q and its conjugate complex, we can rotate the "v" vector this way:

qvq*

The question is, what happens if "v" is not a vector, and is a quaternion? rotates it?
 
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Hi Plott029. In what class are quaternions introduced?
 
quasar987 said:
Hi Plott029. In what class are quaternions introduced?

The utilized to rotations (norm 1, etc.). But the problem I see is that in vectors, I can understand it. But if "v" is a quaternion, I don't understand if the answer is a "rotated quaternion" or another thing.
 
Am i to understand the question is asking what happens if v is a quaternion and not a vector? your wording was a little confusing.

1 method is to find out by expanding the quaternions into there matrix form =].

the 2nd is to just simple understand what's going on...
what happens when you multiple to Qs. Whats does the conjugate
of a quaternion represent

btw is this for a math class or a 3D math/programming class?
 
Plott029 said:
If we take a vector "v" and utilize a quaternion q and its conjugate complex, we can rotate the "v" vector this way:

qvq*

The question is, what happens if "v" is not a vector, and is a quaternion? rotates it?

I thought that qvq^(-1) gives a rotation of a vector v. If v is a general quaternion, then v = v0 + w, with v0 a scalar and w a vector (pure quaternion). Then

qvq^(-1) = v0 + qwq^(-1).

In some sense this can regarded as a rotation of quaternion: the scalar part is invariant under rotation and the vector part gets rotated as ususal.

Regards,
George
 
quaternions

this way, the rotation of a quaternion w is, for example, an expresión like this: qwq(-1) ?
 
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