Describing things for software to read
roy at cacr.caltech.edu
Wed Aug 13 09:19:15 PDT 2003
> Or you might want to query on all filters that have greater than 90%
> transmission over some subrange of their .....
This kind of careful matching is possible in the UCD approach.
Consider these two:
a. If you use a matching function based on string comparison, these do not
match at all, although you might argue that the common substring "phot.flux"
indicates some non-zero matching.
b. However -- if I remebered the speed of light correctly -- these two UCDs
have significant overlap. Therefore a better matching function -- based on
numbers as well as strings -- will evaluate (correctly) to a strong match.
c. As the UCD specification for filters becomes more intricate, we see that
a really sophisticated matching function becomes possible -- as Doug and
Matthew would like to see.
d. NOTE here that nobody has said anything about proper, official,
VO-blessed names for filters or bandpasses. We just build structure that can
deal with the messy, fuzzy, human vocabulary that real astronomers use.
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