VLFeat - Documentation > MATLAB API > GEOMETRY - vl_irodr

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Documentation> MATLAB API> GEOMETRY - vl_irodr

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.

See also: VL_RODR(), VL_HELP().