Kevin Cowtan, University of York, July 2008. Last updated July 2008.

Colophon Tropical bird, supposedly kept as pets by pirates.


'Parrot' is a density modification/phase improvement program, designed as a replacement for 'dm', but more automated and using up-to-date methods. On my JCSG test datasets I get 10% more model built and sequenced after parrot than 'dm', and yet it is runs almost as quickly. Parrot also features automated NCS averaging, using operators from either heavy atom positions, or from a MR or partial model. This code is significantly more reliable than the version in pirate, and faster too.

The latest version of the software is available through the CCP4 update system.

How to run Parrot

After installation the graphical user interface should be available at the bottom of the 'density improvement' module.

For normal calculations, an MTZ file and sequence are required. For NCS averaging, a file of heavy atom coordinates or a partial model are also required in order to determine the NCS operators.

Latest News

Bug fix: the program now works correctly when HL coefficients include missing number flags.
Initial release.