Eric, Thanks, that works perfectly. Phil -- Phillip Cruz, Ph.D. Contractor, Medical Science & Computing Computational Structural Biologist Computational Biology Section Bioinformatics and Computational Biosciences Branch (BCBB) OCICB/OSMO/OD/NIAID/NIH 31 Center Dr., Room 3B62 Bethesda, MD 20892-0485 Office: 301-451-1089 http://bioinformatics.niaid.nih.gov<http://bioinformatics.niaid.nih.gov/> (Within NIH) http://exon.niaid.nih.gov<http://exon.niaid.nih.gov/> (Public) Disclaimer: The information in this e-mail and any of its attachments is confidential and may contain sensitive information. It should not be used by anyone who is not the original intended recipient. If you have received this e-mail in error please inform the sender and delete it from your mailbox or any other storage devices. National Institute of Allergy and Infectious Diseases shall not accept liability for any statements made that are sender's own and not expressly made on behalf of the NIAID by one of its representatives. From: Eric Pettersen <pett@cgl.ucsf.edu<mailto:pett@cgl.ucsf.edu>> Reply-To: "chimera-users@cgl.ucsf.edu<mailto:chimera-users@cgl.ucsf.edu> Mailing List" <chimera-users@cgl.ucsf.edu<mailto:chimera-users@cgl.ucsf.edu>> Date: Thursday, March 19, 2015 4:23 PM To: "Cruz, Phil (NIH/NIAID) [C]" <phil.cruz@nih.gov<mailto:phil.cruz@nih.gov>> Cc: "chimera-users@cgl.ucsf.edu<mailto:chimera-users@cgl.ucsf.edu> Mailing List" <chimera-users@cgl.ucsf.edu<mailto:chimera-users@cgl.ucsf.edu>> Subject: Re: [Chimera-users] Total number of atoms in all submodels On Mar 19, 2015, at 1:16 PM, "Cruz, Phil (NIH/NIAID) [C]" <phil.cruz@nih.gov<mailto:phil.cruz@nih.gov>> wrote: numAtoms = len(openModels.list(modelTypes=[Molecule])[0].atoms) Because of the "[0]" subscript in the above, you are only getting the first Molecule model in the list. Try this: numAtoms = sum([len(m.atoms) for m in openModels.list(modelTypes=[Molecule])]) --Eric Eric Pettersen UCSF Computer Graphics Lab http://www.cgl.ucsf.edu