If no residues are selected to get excluded from analysis (modelfree), an empty file will be created.
This create_empty_unresolved_file_patch file was attached to https://gna.org/task/?6847 by Michael
Bieri (https://gna.org/users/michaelbieri), in the zip file calc_modelfree.py_patch.tar.gz
(https://gna.org/support/download.php?file_id=7750).
