OMIT (CCP4: Supported Program)
NAMEomit - program to calculate omit-maps according to Bhat procedure
SYNOPSISomit HKLIN foo_in.mtz MAPOUT foo_out.map
Note: Memory requirements are governed by a parameter MAXREF set in the program, and this may need to be increased for large problems. If this is the case, the program will hopefully exit gracefully and let you know. Change it as necessary (top of the program source code) and recompile. Increasing MAXREF increases the record lengths for some scratch files, and this can cause problems on some VMS systems. These scratch files are also large in total, which may also cause problems.
LABIN <program label>=<file label>...(Compulsory.)
Program labels are:
SCALE <scale_fobs> <scale_fcalc>(Compulsory.)
<scale_fobs> and <scale_fcalc> are scale factors for Fobs and Fcalc respectively. For example, <scale_fobs> = 2.0 and <scale_fcalc> = -1.0 allows one to calculate a 2FO-FC omit-map.
RESOLUTION <resmin> <resmax>Resolution limits, either 4(sin theta/lambda)**2 or d in Angstrom (either order). If this card isn't given, resolution range will be read from HKLIN.
DLIMIT <dstlmt>Points in the electron density map within <dstlmt> of a symmetry related grid point are set to -RMS density value of the map. Set <dstlmt> = 0.0 for no modification of input map; 3.0-3.5 Angstrom seems a good value otherwise. [Default 3.0]
GRID <nx> <ny> <nz>Number of sampling divisions along each unit cell edge for the output map. The number of points along each axis should be even, and a product of the factors 2, 3, 4 or 5 (each of which may appear any number of times). There is also a maximum value for the number of points set in the program. If any of <nx> <ny> and <nz> do not satisfy these conditions, then they will be reset appropriately. If this keyword is omitted, then the program will choose appropriate values automatically.
TITLE <title><title> will be written to MAPOUT.
Unix example script found in $CEXAM/unix/runnable/
VMS example script found in $CEXAM/vms/
AUTHORProgram written by Bauke Dijkstra (April 1994). firstname.lastname@example.org
Modified by Fred. Vellieux to include histogram mapping and the option of skipping the map truncation step (Feb. 1996).email@example.com
CCP4 modifications made by Martyn Winn (July 1997).firstname.lastname@example.org