rotation2crvΒΆ
Given a rotation matrix \(C^{AB}\) rotating the frame A onto B, the function returns the minimal size Cartesian rotation vector, \(\vec{\psi}\) representing this rotation.
- param Cab
rotation matrix \(C^{AB}\)
- type Cab
np.array
- returns
equivalent Cartesian rotation vector, \(\vec{\psi}\).
- rtype
np.array
Notes
this is the inverse of algebra.crv2rotation for Cartesian rotation vectors
associated to rotations in the range \([-\pi,\,\pi]\), i.e.:
fv == algebra.rotation2crv(algebra.crv2rotation(fv))
for each Cartesian rotation vector of the form \(\vec{\psi} = \psi\,\mathbf{\hat{n}}\)
represented as fv=a*nv such that nv is a unit vector and the scalar a is in the
range \([-\pi,\,\pi]\).