OM = VL_IRODR(R) where R is a rotation matrix computes the the inverse Rodrigues' formula of om, returning the rotation matrix R = dehat(Logm(OM)).

[OM,DOM] = VL_IRODR(R) computes also the derivative of the Rodrigues' formula. In matrix notation this is the expression

       d( dehat logm(vl_hat(R)) )
dom = ----------------------.
d(vec R)^T


[OM,DOM] = VL_IRODR(R) when R is a 9xK matrix repeats the operation for each column (or equivalently matrix with 9*K elements). In this case OM and DOM are arrays with K slices, one per rotation.