what is rotation sequence for the pcregistericp fucntion

Hello,

I am using pcregistericp (https://www.mathworks.com/help/vision/ref/pcregistericp.html) to allign to objects. As an outcome of this function is the transformation matrix which consists of rotation matrix and displacement. What is the sequence of rotation in this matrix of rotation? There are 7 options of sequences of rotation! Does this sequence stay constant from one allignment to another?

I need this information in order to prescribe the rotation of my object in FEA analysis. First, I have to convert the rotation matrix to rotation vector along the axis, by multiplying them, I will get the magnitude of angle along the particular axis! But again, I need to know essential sequence in Rx, Ry and Rz in rotation.

Regards,

Nataliya