Apologies, have been away. I hope I have extracted the relevant points from this thread.
For the record, the CCP4 library also uses the symops to determine the spacegroup, when it can. Hence the observation below that mtzdmp and refmac find the right spacegroup. However there are plenty of cases where the symops are not available, PDB files with CRYST1 card only, user keywords, etc. And there is plenty of independently developed application code which may not follow the library (bearing in mind that we are an anarcho-syndicalist commune etc etc). Ian is right that the surest way of checking the MTZ file is to open in a text editor. You can also edit the SYMINF line this way, though this is probably classed as advanced ccp4 usage... So in my tests SYMINF 4 2 I 4005 'I 1 2 1' PG2 works fine, while SYMINF 4 2 I 5 'I 1 2 1' PG2 shows the problem. And yes, the problem is then MSYMLB3 using the 5 rather than the spacegroup name or the operators. We should be able to fix that. 4005 is for internal usage, converting to 5 on export from the suite. Probably the generating program should have used 4005. Cheers Martyn > My mtz file contains > CELL 148.6099 98.3798 251.9687 90.0000 90.3258 90.0000 > SORT 1 2 3 0 0 > SYMINF 4 2 I 5 'I121' PG2 > SYMM X, Y, Z > SYMM -X, Y, -Z > SYMM X+1/2, Y+1/2, Z+1/2 > SYMM -X+1/2, Y+1/2, -Z+1/2 > RESO 0.0000607290094194 0.1371708661317825 > > So there is a difference, but not the expected one. > My mtz file has exactly the info that should go into the cif headers, > including the space group number of the standard setting: 5. > But mtzdmp and refmac, etc, do manage to find and report the spacegroup > as 4005 from this same file. > Could there be two conflicting spacegroup numbers stored in the header? > > For what it's worth. I see the same behavior on files created by > pointless (re-indexed from C2), files created directly by > mosflm/scala/truncate, and files merged by CAD. > > Ethan -- *********************************************************************** * * * Dr. Martyn Winn * * * * STFC Daresbury Laboratory, Daresbury, Warrington, WA4 4AD, U.K. * * Tel: +44 1925 603455 E-mail: martyn.w...@stfc.ac.uk * * Fax: +44 1925 603825 Skype name: martyn.winn * * URL: http://www.ccp4.ac.uk/martyn/ * ***********************************************************************
