The orthogonal/fractional matrix is outlined here: http://www.iucr.org/__data/assets/pdf_file/0009/7011/19_06_cowtan_coordinate_frames.pdf
Sorry to say I apparently ditched my old Fortran o2f and f2o programs to do that.
Bear in mind, however, that orthogonal has no fixed orientation with respect to fractional - for most space groups "ncode 1" is often used but for primitive monoclinic "ncode 3" is sometimes used, and I think the matrix shown in Kevin Cowtan's document above corresponds to "ncode 1".
Phil Jeffrey Princeton On 9/4/14 3:55 PM, Chen Zhao wrote:
I am sorry, just to clarify, the fractional coordinate matrix I referred to is a rotational matrix in the fractional coordinate system. On Thu, Sep 4, 2014 at 3:52 PM, Chen Zhao <c.z...@yale.edu <mailto:c.z...@yale.edu>> wrote: Hi all, I am just curious whether there are some tools extracting the Euler angles from a fractional coordinate matrix. I have no luck searching it online. Alternatively, I found the analytical solution for the Euler angles from an orthogonal coordinate matrix. So in the worst case, my problem reduces to calculating the transformation matrix between the fractional and orthogonal coordinate system. I feel a little bit at a loss because it is 6 years since I last studied linear algebra. How can I calculate this for a specific unit cell? Thanks a lot in advance! Sincerely, Chen
