Params cannot carry descriptions in VOEvent 1.1

[Matthew Graham]

Hi,

On Mar 26, 2010, at 2:19 PM, Roy Williams wrote:

> Why? What;s wrong? What does "token" mean?
> Can you send follow-up explanation for me and others?
> 
>> Looking at the VOEvent 1.1 schema (I'm at a meeting and wanted something interesting to read), I note:
>> 
>> <xs:complexType name="Param">
>>    <xs:attribute name="name" type="xs:token"/>
>>    <xs:attribute name="ucd" type="xs:token"/>
>>    <xs:attribute name="value" type="xs:string"/>
>>    <xs:attribute name="unit" type="xs:string"/>
>>  </xs:complexType>

OK, this defines exactly what constitutes a Param (from the XML Schema POV). It says that an element of type Param (<Param>) only has four attributes: name, ucd, value and unit; and can contain nothing else. No Description. No Reference.

So:

<Param name="Sun_Distance" value="132.21" unit="deg" ucd="pos.angDistance">
	<Description>Angular distance from the sun to the event position</Description>
</Param>
 
is currently illegal (like dying in the Houses of Parliament).

What it should say is:

<xs:complexType name="Param">
    <xs:choice maxOccurs="unbounded">
      <xs:element name="Description" type="Description"/>
      <xs:element name="Reference" type="Reference"/>
    </xs:choice>
   <xs:attribute name="name" type="xs:token"/>
   <xs:attribute name="ucd" type="xs:token"/>
   <xs:attribute name="value" type="xs:string"/>
   <xs:attribute name="unit" type="xs:string"/>
</xs:complexType>

Oh, and I've just noted that the schema also currently says that elements can be called "Reference" but have no type associated with them. This needs to be corrected as well.

	Cheers,

	Matthew