Re: [Jmol-developers] valid cif file?

[Bob H. <ha...@st...>]

I think

http://www.iucr.org/iucr-top/cif/spec/version1.1/cifsyntax.html#syntax

is pretty clear on this (data_ required):

4. A CIF consists of data names (tags) and associated values organized into data 
blocks. A data block may contain data items (associated data names and data 
values) and/or it may contain save frames.

5. Save frames may only be used in dictionary files.

6. A data block begins with the reserved case-insensitive string data_ followed 
immediately by the name of the data block, forming a data block header....


-------

 From what I can see, "_publ_*" is a data name subset of data_, so files 
beginning with _publ_ before data_ should not be valid either.

Bob Hanson



Miguel wrote:

> My question is about the validity of a CIF file ...
> 
> I have received a file which claims to be a CIF file. The first few lines
> look like:
> 
> 
> ##################################################
> #  mmCIF file created by CS Chem3D
> ##################################################
> 
> 
> 
> ##################################################
> #  sequence section
> #
> 
> loop_
> _entity_poly_seq.entity_id
> _entity_poly_seq.num
> _entity_poly_seq.mon_id
> 
> [snip]
> 
> Note that the first non-comment in this line is loop_
> 
> All of the other .CIF files that I have ever seen either start with data_
> or _publ_
> 
> 
> Q: Can someone who is familiar with CIF tell me whether or not it is valid
> to have a .CIF file that starts with the header above?
> 
> (Jmol does not have a validating .cif parser. I know that iucr is *very*
> concerned about making sure that programs that claim to generate .cif
> files are valid.)
> 
> 
> 
> Miguel

-- 

Robert M. Hanson, ha...@st..., 507-646-3107
Professor of Chemistry, St. Olaf College
1520 St. Olaf Ave., Northfield, MN 55057
mailto:ha...@st...
http://www.stolaf.edu/people/hansonr

"Imagination is more important than knowledge."  - Albert Einstein