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. and ?

herbert_bernstein (yaya@aip.org)
Thu, 28 Sep 95 08:17:51 EDT 

The examples in cifdic.m95 are very clear, but they benefit from a use
of "." which does not seem to agree with the meaning mentioned by
John Westbrook recently, which would be "inappropriate".  Nor does
the "?" seem to help, since, in addition to being jarring in this
context, in most cases the data in question is not "missing", rather
it is intentionally not specified.  Since "intentionally not
specified" is not far in meaning from "inappropriate" and "." works
very well (e.g. in the ATOM_SITE 5HVP example) in this context, I
suggest the keepers of the meanings of such things give their
blessings to the use of "." in this context.

Please note that there is a subtle distinction between a data value
being intentionally not specified in a particular record, and it
being inappropriate to specify a data value for a particular item
in a particular record, especially in deciding whether or not to
revert to implicit default values, but in the examples I have seen
so far in cifdic.m95 that distinction does not seem to cause any
difficulty in interpretation.