A modest proposal for VOEvent

[Roy Williams]

Rob
The most important thing, I think, is that changes to the standard 
require a very good reason.

 From your choices below, the correct choice is clearly to put Params in 
the What section! Because that mechanism is already in the existing 
standard and people (me) have written code and applications with the 
idea that the standard will remain a standard, and not get encrusted 
with special cases. If there is a special XML element for orbital 
eccentricity, then how abut a special element for peak_flux, and a 
special element for magnitude errors, and another one for color of my 
favorite fruit. Where does it stop?

Please don't make arbitrary changes. VOEvent is complex enough already!
Roy



Rob Seaman wrote:
> Again - consensus is the most important thing here.  Simplicity is a 
> close second.  My preference is for orbital elements to appear in 
> WhereWhen, but I could see this moving to What if Params are the 
> consensus, or perhaps Params moving to WhereWhen or perhaps a tidy 
> little bit of dedicated schema.  Would prefer that consensus be 
> arrived at through cogent, not loud, argumentation.
>
> Rob
> ----
>
> On Feb 22, 2009, at 7:00 PM, Roy Williams wrote:
>
>> Perhaps we can use the existing VOEvent structure, with no need to 
>> add any extra schema (see below). The Group type (eg ="ephemeris") 
>> tells the software what Params to expect inside. Everything can be 
>> represented with what we already have!
>>
>> Roy
>>
>> ----------------------------------
>>
>> <What>
>> <Group name="Pluto" type="orbit">
>> <Param name="q"             unit="AU"  dataType="float" value="123" />
>> <Param name="e"                        dataType="float" value="123" />
>> <Param name="i"             unit="deg" dataType="float" value="123" />
>> <Param name="node"          unit="deg" dataType="float" value="123" />
>> <Param name="time_peri_MJD" unit="MJD" dataType="float" value="123" />
>> <Param name="arg_peri"      unit="deg" dataType="float" value="123" />
>> <Param name="epoch"         unit="MJD" dataType="float" value="123" />
>> <Param name="src" value="1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 
>> 19 20 21" />
>> </Group>
>>
>> Then we would add geocentric ephemeris
>>
>> <Group name="E012" type="ephemeris">
>> <Param name="ephem_type"                             
>> value="geocentric"/>
>> <Param name="ra"         unit="deg" dataType="float" value="123" />
>> <Param name="dec"        unit="deg" dataType="float" value="123" />
>> <Param name="mjd"        unit="day" dataType="float" value="123" />
>> </ephemeris>
>>
>> And the detections used to derive the orbit
>>
>> <Group name="D023" type="detections">
>> <Param name="ra"  unit="deg" dataType="float" value="123" />
>> <Param name="dec" unit="deg" dataType="float" value="123" />
>> <Param name="mjd" unit="day" dataType="float" value="123" />
>> <Param name="obscode"                         value="123" />
>> </Group>
>> </What>
>> -- 
>>
>> California Institute of Technology
>> 626 395 3670
>

-- 

California Institute of Technology
626 395 3670