BAND question

[Markus Dolensky]

Hi Alberto, Doug,

... good point. In order to tackle this and another comment received in the DAL
session this week I'd like to put another gray box with a note to section 7.4
which deals with ordered lists and the issue of boundaries:

"Interval and range list query paramaters SHOULD be ordered monotonically.
Interval boundaries are included in the search range. A service SHOULD return
any record inside or just overlapping the search interval. A service SHOULD err
on the side of inclusion thereby leaving the ultimate decision to the consumer
whether to select it for retrieval. A service MAY truncate or compute data to
match the exact boundaries."


One may argue for turning the SHOULDs into MUSTs but this would give service
providers no means to exlude items from a result which would otherwise be
deemend unreasonable for one reason or another. One could also be more specific
depending on the type of data (atlas vs modeled), but I'm not sure being more
verbose is useful.

Cheers,
Markus


Quoting Markus Dolensky <Markus.Dolensky at eso.org>:

> Quoting Alberto Micol <Alberto.Micol at eso.org>:
> 
> > 
> > Hi Doug,
> > 
> > I was trying to understand how I should
> > implement the search engine using the BAND parameter.
> > 
> > Suppose that the query says BAND := 5E-7/5.5E-7
> > 
> > I do have datasets in my archive with a bandpass extending from  
> > 4.8E-7 to 5.1E-7
> > and others with a bandpass going from 5.1E-7 to 5.4E-7.
> > 
> > The first set of datasets hence have a bandpass that intersects the  
> > required one,
> > while the second set has a bandpass that is fully immersed into the  
> > required BAND.
> > 
> > Which ones should I return? Both or only the second set?
> > That is, does intersection suffice?
> > 
> > Or instead should simply be the typical wavelength (central  
> > wavelength however defined)
> > that should match the constraint? (in which case some datasets of my  
> > first set might
> > match and others might not if their central wavelength is defined  
> > differently)
> > 
> > So, shall the data provider work with BOUNDS or LOCATIONs (in char  
> > speak) to answer
> > a BAND query?
> > 
> > Whatever the answer, it would be useful to describe this in the  
> > document,
> > so that we get consistent results from different data centres.
> > 
> > Thanks,
> > 
> > Alberto
> > 
> 
>