Deformation twin - Twin Variants

Given orientation matrices for matrix and twin w.r.t sample frame, how to identify the twin variant activated? For example,
in HCP metals {10-12} tensile twins have 6 variants. In BCC metals, {112}<111> twins have 12 variants.

Thanks!

In order to identify the twin variant activated, you will need to compare the orientation matrices for the matrix and twin with respect to the sample frame. By looking at the orientation matrix for the matrix, you can determine which of the possible variants for the twin is most similar. This can be done by calculating the misorientation angle between the two matrices. The variant with the smallest misorientation angle is the twin variant that is activated.