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Each element has a transformation matrix of the form $$E_{6×6} = \begin{bmatrix} R_{3×3} & [\vec{r}\times] R_{3×3} \\ 0_{3×3} & R_{3×3} \end{bmatrix}$$ where $R_{3×3}$ is the orientation matrix, and $[\vec{r}\times]$ is the 3×3 skew symmetric cross product operator of the element position $\vec{r}$ defined by:  \begin{pmatrix}x\\y\\z ...