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[ccp4bb]: PROGRAM ANNOUNCEMENT: fffear 1.0.0 (groundhog day version)
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fffear 1.0.0: ---- Fast Fourier FEAture Recognition ---
fffear is a program which implements Fast Fourier FEAture Recognition,
as a means to locate molecular fragments in noisy electron
density maps. The method was inspired by Essens (Kleywegt G. J., Jones
T. A., Acta Cryst. D53, 179-185), and re-implemented in reciprocal
space (Cowtan K. D., Acta Cryst. D54, 750-756) to achieve improved
speed and discrimination.
Hopefully this is release is stable and automatic enough for general
users. Differences from beta 0.9.1 include:
1. Search fragment may now be provided as a map rather than an
atomic model. This allows fffear to be used to search for NCS
or cross-crystal operators.
2. Density filters have been implemented to allow matching of the local
means of the fragment and map density. This allows fitting of large
fragments even when there are long range variantions in the electron
density due to missing low-resolution terms. This is particularly
useful for molecular replacement, NCS and cross crystal searches.
3. GRID keyword no longer required.
SEARCH PEAKS keyword allows control of number of fragments found.
SEARCH START keyword allows search for a single orientation.
F000 depracted in favour of FILTER.
4. Speed improvements: cpu times reduced to 70% of previous version.
5. Stability improvements.
The next version will hopefully include the (non-trivial) symmetry
optimisations, which should give a dramatic speedup.
> ftp ftp.ysbl.york.ac.uk
ftp > cd pub/ccp4
ftp > get fffear.tar.gz
ftp > quit
> gunzip fffear.tar.gz
> tar xvf fffear.tar
> cd fffear/src
NOTE: If you wish to use fffear for NCS/cross crystal searches, you
*must* use the latest version of `maprot' with map cutting facilities,
available in the same directory in maputils.tar.gz.