I am posting again as previous identical message had alleged suspicious header.
I used successfully script f=open("prod1-3_no_wat_pop.pdb", "r") for line in f: line=line.rstrip() if "WAT" not in line: print line f.close() to strip lines containing the word WAT from a very long file. A variant need has now emerged, to perform the same task from a very long series of shorter files trp.pdb.1, trp.pdb.2 ,..... Could you see how to adapt the above script to the new need? Or adapt grep -v WAT trp.pdb.1 grep -v WAT trp.pdb.2 .................... grep -v WAT trp.pdb.n Unless you can think better to remove that pervasive molecule of water, to avoid performing the calculation ex novo. Thanks francesco pietra ____________________________________________________________________________________ Be a better friend, newshound, and know-it-all with Yahoo! Mobile. Try it now. http://mobile.yahoo.com/;_ylt=Ahu06i62sR8HDtDypao8Wcj9tAcJ -- http://mail.python.org/mailman/listinfo/python-list