Pwtools for pre- and postprocessing
The pwtools package, written by Steve Schmerler, is a Python package for pre- and postprocessing of atomistic calculations, mostly targeted to Quantum Espresso, CPMD, CP2K and LAMMPS. It has tools extending numpy/scipy and a set of powerful parsers and data types for storing calculation data in a code-agnositc manner, thereby enabling easy comparison and interchange of results from different codes.
This is how one can easily read in a dcd trajectory that was written by CP2K:
$ python >>> from pwtools import dcd >>> cc,co = dcd.read_dcd_data('cp2k.dcd')
cc will contain the unit cell parameters for each step (a,b,c,alpha,beta,gamma), and
co will contain the Cartesian coordinates in Angstrom.