Convert rotation from matrix to axis-angle representation
r = vrrotmat2vec(m)
r = vrrotmat2vec(m,options)
r = vrrotmat2vec(m) returns
an axis-angle representation of rotation defined by the rotation matrix
r = vrrotmat2vec(m,options) converts
the rotation with the default algorithm parameters replaced by values
options structure contains the parameter
represents the value below which a number will be treated as zero
(default value is 1e-12).
r is a four-element axis-angle
rotation row vector. The first three elements specify the rotation
axis, and the last element defines the angle of rotation.