Databases
StackOverflow2013
Postsdbo
PO
 

Note that there are some explanatory texts on larger screens.

plurals
  1. PO
    primarykey
    data
    text
    <p>As others have already pointed out, your question should be revised. Let's call your vectors <code>a</code> and <code>b</code>. I assume that <code>length(a)==length(b) &gt; 0</code> otherwise I cannot answer the question.</p> <hr> <p>Calculate the <a href="http://en.wikipedia.org/wiki/Cross_product#Coordinate_notation" rel="nofollow noreferrer">cross product</a> of your vectors <code>v = a x b</code>; <code>v</code> gives the <strong>axis</strong> of rotation. By computing the <a href="http://en.wikipedia.org/wiki/Dot_product#Algebraic_definition" rel="nofollow noreferrer">dot product</a>, you can get the cosine of the <strong>angle</strong> you should rotate with <code>cos(angle)=dot(a,b)/(length(a)length(b))</code>, and with <code>acos</code> you can uniquely determine the angle (@Archie thanks for pointing out my earlier mistake). At this point you have the <strong>axis angle representation</strong> of your rotation.</p> <p>The remaining work is to convert this representation to the representation you are looking for: Euler angles. <a href="http://www.euclideanspace.com/maths/geometry/rotations/conversions/angleToEuler/index.htm" rel="nofollow noreferrer">Conversion Axis-Angle to Euler</a> is a way to do it, as you have found it. You have to handle the degenerate case when <code>v = [ 0, 0, 0]</code>, that is, when the angle is either 0 or 180 degrees.</p> <hr> <p>I personally don't like Euler angles, they screw up the stability of your app and they are not appropriate for interpolation, see also</p> <ul> <li><p><a href="https://stackoverflow.com/q/5577334/341970">Strange behavior with android orientation sensor</a></p></li> <li><p><a href="https://stackoverflow.com/q/5580283/341970">Interpolating between rotation matrices</a></p></li> </ul>
    singulars
    1. This table or related slice is empty.
    1. POEuler angles between two 3d vectors
      singulars
      1. PTQuestion
    1. PTAnswer
    1. USCommunity
    1. USAli
    plurals
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTUpMod
    2. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTUpMod
    1. COCross production is not enough - it won't distinguish 0 and 180 degrees angles. You should compute both: cross to get a sine and scalar to get a cosine, and then use both of them to compute the angle (for instance via atan2() function in C math library).
      singulars
      1. PO
      1. USArchie
    2. COWhat do you think of this method:http://www.euclideanspace.com/maths/geometry/rotations/conversions/angleToEuler/index.htm
      singulars
      1. PO
      1. UStomyake
    3. CO@Archie Yes, correct, fixed. Actually the dot product and `acos` is enough.
      singulars
      1. PO
      1. USAli
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload