Discussion List Archives

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: Variants

David Brown wrote:
> Is a CIF a fixed archive, a place 
> where we entomb a fact of nature, or is it an evolving document that 
> carries it own history along with it?

CIF is becoming the standard data format for working crystallography 
experiments, not just an archival format. Maybe the goal should be that 
_variant components can be removed from archival CIFs, in a way that 
does not complicate non-variant data.

To me, the _diffrn_radiation_wavelength_determinaton approach is 
confusing. The wavelength id is defined mainly for multiple wavelength 
experiments. Using _variant, multiple wavelengths might be defined like 

                 1   final   1.23456
                 1   prelim   1.25
                 2   final   1.00

Some suggestions:

Maybe use "_variant_id" instead of "_variant_variant"?

Maybe the _variant_* items should include an identifier as to what 
primary value is being varied, when one exists. In this case, the 
wavelength value is the primary varying value, and all others are derived.

Joe Krahn

comcifs mailing list

Reply to: [list | sender only]
International Union of Crystallography

Scientific Union Member of the International Science Council (admitted 1947). Member of CODATA, the ISC Committee on Data. Partner with UNESCO, the United Nations Educational, Scientific and Cultural Organization in the International Year of Crystallography 2014.

International Science Council Scientific Freedom Policy

The IUCr observes the basic policy of non-discrimination and affirms the right and freedom of scientists to associate in international scientific activity without regard to such factors as ethnic origin, religion, citizenship, language, political stance, gender, sex or age, in accordance with the Statutes of the International Council for Science.