Resulting rot. vector from rot. matrix

Hi all,

I’m in trouble with some math stuff rather than blender or python stuff this time. Hopefully somebody can point me a way…

I have the rotation matrix (via the object matrix) of an object. I also have the euler angels.

What I need is a vector which describes the resulting rotation axis of the rotation. Additionaly needed is the angel which the object rotates around this axis.

I’m totaly stucked on this for hours now…