IVOA Simple Line Access Protocol v0.2

[Doug Tody]

Hi Markus -

I hadn't thought of it that way, but as you say a range list can be viewed
either in terms of inclusion or exclusion.

For the rest of you, in our cube use case we want to do 1D spectrum
extraction in a source-free region to fit the sky background, and then
collapse the cube along the spectral axis, excluding spectral regions
containing emission lines in the sky spectrum.

 	- Doug



On Thu, 9 Feb 2006, Markus Dolensky wrote:

> Hi Doug,
>
> Can't see anything wrong with it. As discussed off-line we may have also 
> cases where we whish to express an exclusion of range(s) when collapsing 
> cubes and that seems to work just fine as in this example:
>
> "smaller than 1 or between 3 and 5 or bigger than 7" would be become
>
> param = :1,3:5,7:
>
> (right?)
>
> Cheers,
> Markus
>
>
>
> Doug Tody wrote:
>> A simple approach to range lists which requires only a slight departure
>> from what is currently done in SIA (POS) and proposed for SSA is to keep
>> "," as the list delimiter but switch to another metacharacter, ":" perhaps,
>> for ranges.  Then we have
>>
>>     param = x                equality
>>     param = x:y                closed range
>>     param = x:                open range
>>     param = x,y                list
>>     param = x,a:b,y            range list
>>     etc.
>