Re: Restricting input depending on output

This just has to be the world's worst way of indicating equality....

Whatever happened to variables? (I know, but its a rhetorical question)

Frank McCabe

On Tuesday, March 11, 2003, at 07:40  AM, Saied Tazari wrote:

>
> Drew McDermott wrote:
>>    [Saied Tazari]
>> >  I am working on a user-centric broker agent in the context of a 
>> national >  research project in Germany (see the extended abstract 
>> submitted to KIMAS'03 >  for a summary of our ideas about the broker 
>> agent under >  
>> http://www.zgdv.de/departments/z3/Z3Staff/stazari/index_html_en).
>> >
>> >  I have a problem regarding the flow control in composite processes 
>> (more >  precisely in a simple sequence without any preconditions and 
>> effects):  How >  can I specify that one of the inputs of an atomic 
>> process must be a subset >  of one of the outputs of the preceeding 
>> atomic process?
>> >
>> >  Consider the following example:
>> >  >  ...
>> >
>> >  How can I formulate that a concrete value given for 
>> selectedLocationList_In >  within a concrete sequence of these two 
>> processes must be a subset of the >  concrete value delivered for 
>> availableLocationList_Out?
>> We have a technique in DAML-S for indicating that the two values must
>> be identical:
>>    <rdf:Description rdf:about="...whole process id...">
>>       <process:sameValues rdf:parsetype="daml:collection">
>>          <process:ValueOf             
>> process:atClass="#GetPostitCompositionPrerequisites"
>>             process:theProperty="#availableLocationList_Out"/>
>>          <process:ValueOf             process:atClass="#StickPostit"
>>             process:theProperty="#selectedLocationList_In"/>
>>       </process:sameValues>
>>    </rdf:Description>
>> However, what you want is slightly different.
>
> That's true, namely I would like to have something like 'subsetOf' 
> instead of 'sameValues'.  Besides, in my point of view the implicit 
> assumption in the above description that "we mean only those instances 
> of GetPostitCompositionPrerequisites and StickPostit that appear in 
> the one instance of the sequence containing both of those" must be 
> made explicit.
>
>> Why not introduce a
>> "select" step that picks one from a list?  Then you could have a 
>> sequence
>>     GetPostitCompositionPrerequisites
>>             >out>  availableLocationList_Out
>>             =availableLocationList_In
>>              >in>
>>                PickOne
>>                  >out>  selectedLocationList_Out
>>                        =selectedLocationList_In
>>                           >=>                               
>> StickPostit
>> You would need two 'sameValues' declarations to make this work.
>>                                              -- Drew McDermott
>
> Two problems:
>
> . That is shifting the problem from
>      (availableLocationList_Out --here--> selectedLocationList_In)
>   to
>      (availableLocationList_In --here--> selectedLocationList_Out)
>   despite making the sequence longer.
>
> . The natural meaning of PickOne says that only one location is
>   selected but our requirement is that the value to be provided
>   for selectedLocationList_In must be a **subset** of the value
>   provided for availableLocationList_Out in the preceeding step.
>
> -- Saied Tazari
>

Received on Tuesday, 11 March 2003 12:24:46 UTC