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 <[log in to unmask]
> <mailto:[log in to unmask]>> 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
>
>
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