Pose blend shape vector (207) about romp HOT 3 CLOSED

Pose blend shapes. We denote as R : R|✓
~| 7! R9K a function
that maps a pose vector ~✓ to a vector of concatenated part relative
rotation matrices, exp(~!). Given that our rig has 23 joints, R(~✓) is
a vector of length (23 ⇥ 9 = 207). Elements of R(~✓) are functions
of sines and cosines (Eq. (1)) of joint angles and therefore R(~✓) is
non-linear with ~✓.

transform_rot_representation(pose.reshape(-1,3), input_type='vec',out_type='mat')