title: Rodrigues into Eulerangles and vice versa
body: <p>I am useing solvePnP and i am getting a translation vector. 
  Now i need to compare some euler angles with those results from solvePnP.
  And i want/need to transfer the euler angles into "rodrigues";</p>
  
  <p>Is the translation vector from solvePnP equal to euler angles. 
  Is the translation matrix the only thing what has to do with Rodrigues? 
  or are there special rodrigues angles which are totaly different to the 3 euler angles?
  How is the math between both? 
  Is there an OpenCV function which i couldn't find? </p>