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Hi Kris,<br>your questions isn't simple and the solution isn't straightforward.<br>The functionality you are looking for isn't implemented in the cctbx.<br>You are right in your assumption that most of what you need<br>is already available, but there are missing pieces.<br>Given a unit cell (your primitive vectors), the cctbx can give you<br>the corresponding highest point-group symmetry (lattice symmetry)<br>in a very robust way, but there is nothing to loop over the<br>compatible space groups and to check if the symmetry operations<br>are compatible with the coordinates.<br>There are some programs out there which do this. I think Ton Spek's<br>PLATON for example. The Superflip program (google) determines the symmetry<br>from a P1 map. There is also J. Appl. Cryst. (2005). 38, 237-238 and<br>J. Appl. Cryst. (1998). 31, 922-928. There may be more. I haven't<br>followed the developments very closely.<br>
An idea that has been floating around in my mind for a long time is<br>to use the fast translation function. Make a map given your coordinates,<br>loop over all space group, use the fast translation function to find<br>the origin. This is implemented in phenix.hyss. It should be relatively<br>easy to adapt this implementation for your purpose. You'd get<br>scores (correlation coefficients) instead of yes/no answers. This<br>could be useful to uncover approximate symmetry, but I'm just guessing.<br>If you want to try implementations yourself, I'd be happy to<br>answer specific questions.<br>Ralf<br><br></div></div><br>
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