[sdpd] Re: Use of CIF as advocated by Lachlan

[Robin Shirley <R.Shirley... @surrey.ac.uk>]

Lachlan Cranswick writes [Fri, 5 Nov 1999 17:59:40 +0000 (GMT)]:

> While the database system Armel has done looks good,,
> this still leaves the problem of a common file
> format.  If CIF was used, many of the problems/requests
> described by Andrew would become non-issues.

I'm reluctant to take issue with Lachlan, who does such a good job at 
the CCP14 website, and indeed publishes CRYSFIRE from there.

However, I have to say that I'd feel happier about supporting CIF as a common
file format if (a) it were considerably simpler to read and (b) the CIF
committee were more responsive to practical powder-related issues.

Firstly let me say that, in a spirit of general co-operation, several years
ago I extended CRYS/CRYSFIRE to support a basic form of CIF as a file-save
option (i.e. for output).

However I can't support it as an input format due to its excessive
complexity.  I simply don't have the address space available in CRYS, and
most of what's included in CIF would be irrelevant for this purpose.

Also, my attitude is partly coloured by the fact that, both at Beijing in 
1993 and at Seattle in 1996, I submitted a formal proposal concerning a small 
set of Powder-CIF extensions which would cover issues connected with indexing
(copies emailed on request), as at present these are not touched on.

On each occasion I took the precaution of first running them past Brian Toby 
to confirm that their syntax was well formed.  And both times absolutely 
nothing happened.  I didn't even receive the courtesy of an acknowledgement.

Brian told me at Seattle that the committee seemed to have lost the 1993
proposals.  After resubmitting them, I again got no reply, so I didn't bother
trying again at Edinburgh.

In the light of this, I'm afraid that as a software author I don't feel
encouraged to put myself out to support CIF as a common file format, when
the CIF committee rather gives the impression of living in an ivory tower 
remote from actual users.

Robin Shirley
School of Human Sciences
University of Surrey
UK