ccp2fsfour
[software] CCP2FSFOUR
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Converts a CCP4-style map to an XtalView FSFOUR-style map.




program availability  
 

ccp2fsfour is available in binary form for download.
ccp2fsfour usage  
 

ccp2fsfour reads CCP4 version maps (tested up to CCP4 v. 3.5) and writes them out into the XtalView FSFOUR-style.

ccp2fsfour <CCP4 input map> <xtalview output map>

It is important to know that the FSFOUR format maps (and XtalView) assume that there is an entire unit cell written to the file. In the current version, the map that is written out is expanded to the entire unit cell, but the density is not copied in a crystallographic way to cover the whole cell.

For the moment, CCP4 maps should be pre-expanded through the CCP4 program mapmask using the following cards:

  • XYZLIM 0.0 1.0 0.0 1.0 0.0 1.0
  • EXTEND XTAL



    • xtalview instructions  
     

    When reading in (any) FSFOUR maps into XtalView, right-click on the Load/write Map button under the Files... dialog and choose "Load Fsfour Format Map (*.map)". Simply choosing the default (reading the file as if it were a text phase file) won't work.





    bug list  
     

    There are a few incompatibilities that need to be addressed in new versions that should make the conversion robust.

  • Handle expansion of maps containing fragments of the asymmetric unit into a full cell.

  • Handle skew transformations from the CCP4 map header.

  • The FSFOUR format doesn't have a machine stamp analogous to the one in CCP4 map header. This means that the output map is byte-order dependent. Thus one should run ccp2fsfour on the architecture that XtalView is going to be run. (This is a FSFOUR-format limitation rather than a bug in ccp2fsfour.)





    		•
    history  
     

  • 1.03b Fix compilation bug where PowerPC MacOSX was compiled as a little-endian architecture.
  • 1.03 Fix missing information fsfour header for non-XtalView usage.
  • 1.02 Recompile to fix bizarre issue in SunOS version.
  • 1.01 Fixed off-by one error at map edge.
  • 1.0 Initial release.





    • a final word  
     

    As always, I've only extensively tested this program against many of the things that I do regularly so there are potentially a number of bugs that are creeping about. I've written the program to be very robust so that it should survive even fairly pathological cases, but I've only checked a finite number of these. If you run into any problems, feel free to e-mail me and depending on the problem (and my schedule) I might crack open the code and fix them.

    Praise and requests for options that would be useful are also welcome.







    Christopher Putnam, Ph.D.
    cdputnam@scripps.edu
    The Scripps Research Institute
    Last Updated: 06/01/07