Procrustes alignment in SPHARM PDM

Hi,
In the spharm-pdm,alignment of two object using rigid procrustes alignment ,an article mentioned that this rigid procrustes alignment procedure computer an optimal linear geometric transformation that best maps the shape changes between the two object based in the established correspondence.I wonder where is the transformation and how to get the transnational and rotational differences as follow picture.

who can give me instructions,please