Re: [dotNetRDF-bugs] Scope of autassigned bland node IDs

[Rob V. <rv...@do...>]

I have now fixed the brute force generator and added unit tests specifically
for it so as to verify that it does generate all possible mappings

I will close out CORE-345 since this should now be completely resolved

Rob

From:  Rob Vesse <rv...@do...>
Reply-To:  dotNetRDF Bug Report tracking and resolution
<dot...@li...>
Date:  Friday, April 12, 2013 2:14 PM
To:  dotNetRDF Bug Report tracking and resolution
<dot...@li...>
Subject:  Re: [dotNetRDF-bugs] Scope of autassigned bland node IDs

> Hey Tom
> 
> So I validated that those graphs were indeed equal
> 
> Having gone through that process by hand I realized there was an additional
> rules based mapping step we could be using that we weren't, with this in place
> we now don't have to use the divide and conquer approach on any of your test
> cases which will improve performance.
> 
> All your tests cases now pass, if you come up with any more please go ahead
> and add them.
> 
> I will try and look more to figure out if the brute force generator is
> generating sensible mappings but hopefully now very few graphs should ever
> have to resort to that approach.
> 
> Rob
> 
> From:  Rob Vesse <rv...@do...>
> Reply-To:  dotNetRDF Bug Report tracking and resolution
> <dot...@li...>
> Date:  Friday, April 12, 2013 12:37 PM
> To:  dotNetRDF Bug Report tracking and resolution
> <dot...@li...>
> Subject:  Re: [dotNetRDF-bugs] Scope of autassigned bland node IDs
> 
>> Yes I realized that when I tried a pull again after sending the reply
>> 
>> Ok so that case is bombing out on brute force mapping which would tend to
>> indicate that there may be an issue there still
>> 
>> At a glance the graphs look equivalent but I need to verify this by hand
>> because the sub-graphs are too large and blank node heavy to easily verify
>> whether they are equal and we are just not detecting it correctly or if they
>> are non-equal
>> 
>> Rob
>> 
>> From:  Tomek Pluskiewicz <to...@pl...>
>> Reply-To:  dotNetRDF Bug Report tracking and resolution
>> <dot...@li...>
>> Date:  Friday, April 12, 2013 12:05 PM
>> To:  dotNetRDF Bug Report tracking and resolution
>> <dot...@li...>
>> Subject:  Re: [dotNetRDF-bugs] Scope of autassigned bland node IDs
>> 
>>> 
>>> I did with a little delay. Please check now.
>>> 
>>> Tom
>>> 
>>> On Apr 12, 2013 8:59 PM, "Rob Vesse" <rv...@do...> wrote:
>>>> Ok
>>>> 
>>>> Can you push the commits up so I can pull them down and take a look at the
>>>> new test cases
>>>> 
>>>> Rob
>>>> 
>>>> On 4/12/13 11:55 AM, "Tomasz Pluskiewicz" <tom...@gm...>
>>>> wrote:
>>>> 
>>>>> >I've just committed more test cases. Out of the 6 none fail cause OOM
>>>>> >anymore, which is marvellous.
>>>>> >
>>>>> >However case1 reports false but I'm positive these graphs are actually
>>>>> >equal.
>>>>> >
>>>>> >Thanks,
>>>>> >Tom
>>>>> >
>>>>> >On Fri, Apr 12, 2013 at 8:33 PM, Rob Vesse <rv...@do...> wrote:
>>>>>> >> Those would be useful
>>>>>> >>
>>>>>> >> Btw I closed the issue branch so please just add the tests to default
>>>>>> >>
>>>>>> >> Rob
>>>>>> >>
>>>>>> >> On 4/12/13 11:23 AM, "Tomasz Pluskiewicz"
>>>>>> <tom...@gm...>
>>>>>> >> wrote:
>>>>>> >>
>>>>>>> >>>Hi Rob
>>>>>>> >>>
>>>>>>> >>>Thanks so much. And yes, I do have 4 or 5 cases which stumble on this
>>>>>>> >>>same issue. I will add all these to the test fixture.
>>>>>>> >>>
>>>>>>> >>>Tom
>>>>>>> >>>
>>>>>>> >>>On Fri, Apr 12, 2013 at 8:20 PM, Rob Vesse <rv...@do...>
>>>>>>> wrote:
>>>>>>>> >>>> Hey Tom
>>>>>>>> >>>>
>>>>>>>> >>>> This should now be fixed for your test case though I am not 100%
>>>>>>>> >>>>convinced
>>>>>>>> >>>> that brute forcing is not still broken
>>>>>>>> >>>>
>>>>>>>> >>>> What I have done to fix this is to add an intermediate step
>>>>>>>> between
>>>>>>>> >>>>the
>>>>>>>> >>>> rules based and brute force mapping which does a divide and
>>>>>>>> conquer
>>>>>>>> >>>> approach
>>>>>>>> >>>>
>>>>>>>> >>>> What this does is break the unmapped blank node portions of the
>>>>>>>> graph
>>>>>>>> >>>>into
>>>>>>>> >>>> its constituent isolated sub-graphs (those that share no blank
>>>>>>>> nodes)
>>>>>>>> >>>>and
>>>>>>>> >>>> then recursively calls Equals() on the candidate matches for the
>>>>>>>> >>>> sub-graphs.  This approach reduces the amount of work required and
the
>>>>>>>> >>>> likelihood of needing to brute force at all though we still fall
back
>>>>>>>> >>>>in
>>>>>>>> >>>> the worst case.
>>>>>>>> >>>>
>>>>>>>> >>>> If you can come up with any more graphs that break GraphMatcher
>>>>>>>> those
>>>>>>>> >>>> would be much appreciated
>>>>>>>> >>>>
>>>>>>>> >>>> Rob
>>>>>>>> >>>>
>>>>>>>> >>>> On 4/12/13 10:25 AM, "Rob Vesse" <rv...@do...> wrote:
>>>>>>>> >>>>
>>>>>>>>> >>>>>s/not/now
>>>>>>>>> >>>>>
>>>>>>>>> >>>>>That should be "the test will now complete within the timeout"
>>>>>>>>> >>>>>
>>>>>>>>> >>>>>Rob
>>>>>>>>> >>>>>
>>>>>>>>> >>>>>On 4/12/13 10:23 AM, "Rob Vesse" <rv...@do...> wrote:
>>>>>>>>> >>>>>
>>>>>>>>>> >>>>>>Hey Tom
>>>>>>>>>> >>>>>>
>>>>>>>>>> >>>>>>So the logic for generating the brute force mappings was
>>>>>>>>>> completely
>>>>>>>>>> >>>>>>broken
>>>>>>>>>> >>>>>>causing it to get stuck in a memory sucking spin cycle :(
>>>>>>>>>> >>>>>>
>>>>>>>>>> >>>>>>I rewrote the GenerateMappings() method from scratch to use
yield
>>>>>>>>>> >>>>>>return
>>>>>>>>>> >>>>>>and the test will not complete within the timeout but it fails
so I
>>>>>>>>>> >>>>>>still
>>>>>>>>>> >>>>>>need to dig further
>>>>>>>>>> >>>>>>
>>>>>>>>>> >>>>>>We may still be generating incorrect possible mappings or the
logic
>>>>>>>>>> >>>>>>for
>>>>>>>>>> >>>>>>brute force may be flawed elsewhere
>>>>>>>>>> >>>>>>
>>>>>>>>>> >>>>>>Rob
>>>>>>>>>> >>>>>>
>>>>>>>>>> >>>>>>On 4/9/13 10:34 AM, "Rob Vesse" <rv...@do...> wrote:
>>>>>>>>>> >>>>>>
>>>>>>>>>>> >>>>>>>Hey Tom
>>>>>>>>>>> >>>>>>>
>>>>>>>>>>> >>>>>>>The problem is that graph isomorphism is NP-hard so sometimes
the
>>>>>>>>>>> >>>>>>>only
>>>>>>>>>>> >>>>>>>option we have is to attempt to brute force the problem
>>>>>>>>>>> >>>>>>>
>>>>>>>>>>> >>>>>>>I've started added some Debug.WriteLine() to GraphMatcher to
track
>>>>>>>>>>> >>>>>>>down
>>>>>>>>>>> >>>>>>>where things go wrong
>>>>>>>>>>> >>>>>>>
>>>>>>>>>>> >>>>>>>For your graphs they may look trivially equal but to code
>>>>>>>>>>> they are
>>>>>>>>>>> >>>>>>>not,
>>>>>>>>>>> >>>>>>>the reason this worked prior to 0.8.0 is that one of the
>>>>>>>>>>> things we
>>>>>>>>>>> >>>>>>>try
>>>>>>>>>>> >>>>>>>is
>>>>>>>>>>> >>>>>>>a trivial mapping (assume blank nodes have same IDs in both
>>>>>>>>>>> graphs)
>>>>>>>>>>> >>>>>>>so
>>>>>>>>>>> >>>>>>>in
>>>>>>>>>>> >>>>>>>previous releases you would likely have hit this case and
>>>>>>>>>>> been fine.
>>>>>>>>>>> >>>>>>>
>>>>>>>>>>> >>>>>>>You have 33 blank nodes in the graph of which only 6 are
>>>>>>>>>>> uniquely
>>>>>>>>>>> >>>>>>>identifiable and mappable.  The matcher generates a candidate
>>>>>>>>>>> >>>>>>>mapping
>>>>>>>>>>> >>>>>>>for
>>>>>>>>>>> >>>>>>>the whole graph but its best effort is incorrect, so then it
falls
>>>>>>>>>>> >>>>>>>back
>>>>>>>>>>> >>>>>>>to
>>>>>>>>>>> >>>>>>>brute force.  I need to dig further into whether the
>>>>>>>>>>> candidate
>>>>>>>>>>> >>>>>>>mapping
>>>>>>>>>>> >>>>>>>could be improved but this is not trivial to debug and will
take
>>>>>>>>>>> >>>>>>>some
>>>>>>>>>>> >>>>>>>time
>>>>>>>>>>> >>>>>>>to resolve.
>>>>>>>>>>> >>>>>>>
>>>>>>>>>>> >>>>>>>We may be able to reduce the "memory leak" by using yield
rather
>>>>>>>>>>> >>>>>>>than
>>>>>>>>>>> >>>>>>>pre-generating all possible mapping but this is a tricky
>>>>>>>>>>> refactor,
>>>>>>>>>>> >>>>>>>it's
>>>>>>>>>>> >>>>>>>been a long time since I wrote the code originally and I
>>>>>>>>>>> remember
>>>>>>>>>>> >>>>>>>that
>>>>>>>>>>> >>>>>>>doing the mapping in the yield form proved thorny at the time
so I
>>>>>>>>>>> >>>>>>>chose
>>>>>>>>>>> >>>>>>>not to.  The code itself for generating the mappings has some
>>>>>>>>>>> >>>>>>>slightly
>>>>>>>>>>> >>>>>>>strange things in it so I really need to spend a block of
time
>>>>>>>>>>> >>>>>>>refreshing
>>>>>>>>>>> >>>>>>>myself on the logic there to check that it is sound before I
>>>>>>>>>>> attempt
>>>>>>>>>>> >>>>>>>to
>>>>>>>>>>> >>>>>>>refactor.
>>>>>>>>>>> >>>>>>>
>>>>>>>>>>> >>>>>>>Rob
>>>>>>>>>>> >>>>>>>
>>>>>>>>>>> >>>>>>>On 4/7/13 11:20 AM, "Tomasz Pluskiewicz"
>>>>>>>>>>> >>>>>>><tom...@gm...>
>>>>>>>>>>> >>>>>>>wrote:
>>>>>>>>>>> >>>>>>>
>>>>>>>>>>>> >>>>>>>>Hm, I was wrong actually.
>>>>>>>>>>>> >>>>>>>>
>>>>>>>>>>>> >>>>>>>>I tried comparing the exact same graphs loaded from Turtle
in
>>>>>>>>>>>> >>>>>>>>dotNetRDF test project but I got the unit test wrong.
>>>>>>>>>>>> >>>>>>>>
>>>>>>>>>>>> >>>>>>>>I have added the CORE-345 bug and committed a failing test
case
>>>>>>>>>>>> >>>>>>>>[1].
>>>>>>>>>>>> >>>>>>>>Could you please have a look at this?
>>>>>>>>>>>> >>>>>>>>
>>>>>>>>>>>> >>>>>>>>Thanks,
>>>>>>>>>>>> >>>>>>>>Tom
>>>>>>>>>>>> >>>>>>>>
>>>>>>>>>>>> >>>>>>>>[1]:
>>>>>>>>>>>> 
>>>>>>>>https://bitbucket.org/dotnetrdf/dotnetrdf/commits/branch/CORE-345
>>>>>>>>>>>> >>>>>>>>
>>>>>>>>>>>> >>>>>>>>On Sun, Apr 7, 2013 at 7:36 PM, Tomasz Pluskiewicz
>>>>>>>>>>>> >>>>>>>><tom...@gm...> wrote:
>>>>>>>>>>>>> >>>>>>>>> Hi Rob
>>>>>>>>>>>>> >>>>>>>>>
>>>>>>>>>>>>> >>>>>>>>> I finally got back to R2RML to analyze why I am getting
that
>>>>>>>>>>>>> >>>>>>>>>memory
>>>>>>>>>>>>> >>>>>>>>> leak. It seems connected to the changes you had to
>>>>>>>>>>>>> introduce for
>>>>>>>>>>>>> >>>>>>>>> SPARQL 1.1.
>>>>>>>>>>>>> >>>>>>>>>
>>>>>>>>>>>>> >>>>>>>>> I have determined that it happens in
>>>>>>>>>>>>> >>>>>>>>>GraphMatcher#GenerateMappings
>>>>>>>>>>>>> >>>>>>>>> method. The graphs are equal and I'm not sure what
>>>>>>>>>>>>> causes the
>>>>>>>>>>>>> >>>>>>>>>problem.
>>>>>>>>>>>>> >>>>>>>>> As soon as TryBruteForceMapping is reached memory
>>>>>>>>>>>>> consumption
>>>>>>>>>>>>> >>>>>>>>>explodes
>>>>>>>>>>>>> >>>>>>>>> to gigabytes within minutes.
>>>>>>>>>>>>> >>>>>>>>>
>>>>>>>>>>>>> >>>>>>>>> The low-level problem is the mappings variable in the
>>>>>>>>>>>>> >>>>>>>>> GenerateMappings, which within a few iteration contains
thousands
>>>>>>>>>>>>> >>>>>>>>>of
>>>>>>>>>>>>> >>>>>>>>> elements.
>>>>>>>>>>>>> >>>>>>>>>
>>>>>>>>>>>>> >>>>>>>>> This problem no longer occurs on trunk. Have you
>>>>>>>>>>>>> actually been
>>>>>>>>>>>>> >>>>>>>>> introducing any fixes around that area?
>>>>>>>>>>>>> >>>>>>>>>
>>>>>>>>>>>>> >>>>>>>>> Tom
>>>>>>>>>>>>> >>>>>>>>>
>>>>>>>>>>>>> >>>>>>>>> On Mon, Jan 14, 2013 at 12:32 PM, Rob Vesse
>>>>>>>>>>>>> >>>>>>>>><rv...@do...>
>>>>>>>>>>>>> >>>>>>>>>wrote:
>>>>>>>>>>>>>> >>>>>>>>>> Comments inline:
>>>>>>>>>>>>>> >>>>>>>>>>
>>>>>>>>>>>>>> >>>>>>>>>> On 1/10/13 7:14 PM, "Tomek Pluskiewicz"
>>>>>>>>>>>>>> <to...@pl...>
>>>>>>>>>>>>>> >>>>>>>>>>wrote:
>>>>>>>>>>>>>> >>>>>>>>>>
>>>>>>>>>>>>>>> >>>>>>>>>>>Hi Rob
>>>>>>>>>>>>>>> >>>>>>>>>>>
>>>>>>>>>>>>>>> >>>>>>>>>>>I have just updated to latest dotNetRDF available on
NuGet and
>>>>>>>>>>>>>>> >>>>>>>>>>>I'm
>>>>>>>>>>>>>>> >>>>>>>>>>>experiencing two issues.
>>>>>>>>>>>>>>> >>>>>>>>>>>
>>>>>>>>>>>>>>> >>>>>>>>>>>1. In my unit tests I relied on the way the library
assigns
>>>>>>>>>>>>>>> >>>>>>>>>>>blank
>>>>>>>>>>>>>>> >>>>>>>>>>>node
>>>>>>>>>>>>>>> >>>>>>>>>>>identifiers: autos1, autos2 and so on. When I run the
tests
>>>>>>>>>>>>>>> >>>>>>>>>>>separately
>>>>>>>>>>>>>>> >>>>>>>>>>>each one passes but when I batch them they fail
because in
>>>>>>>>>>>>>>> >>>>>>>>>>>subsequent
>>>>>>>>>>>>>>> >>>>>>>>>>>tests blank nodes are name autos2, autos3, etc.
>>>>>>>>>>>>>>> However they
>>>>>>>>>>>>>>> >>>>>>>>>>>don't
>>>>>>>>>>>>>>> >>>>>>>>>>>share the same graph or triple store. Have you
>>>>>>>>>>>>>>> changed this
>>>>>>>>>>>>>>> >>>>>>>>>>>behavior
>>>>>>>>>>>>>>> >>>>>>>>>>>delbierately?
>>>>>>>>>>>>>> >>>>>>>>>>
>>>>>>>>>>>>>> >>>>>>>>>> Yes this behavior changed in the 0.8.x releases, the
change was
>>>>>>>>>>>>>> >>>>>>>>>>made
>>>>>>>>>>>>>> >>>>>>>>>>in
>>>>>>>>>>>>>> >>>>>>>>>> order to resolve a bug in SPARQL 1.1 Update support
and also
>>>>>>>>>>>>>> >>>>>>>>>>uncovered
>>>>>>>>>>>>>> >>>>>>>>>>a
>>>>>>>>>>>>>> >>>>>>>>>> bug in graph isomorphism calculation which was fixed.
>>>>>>>>>>>>>> >>>>>>>>>>
>>>>>>>>>>>>>> >>>>>>>>>> You shouldn't rely on an internal implementation
>>>>>>>>>>>>>> detail like how
>>>>>>>>>>>>>> >>>>>>>>>>the
>>>>>>>>>>>>>> >>>>>>>>>> library assigns blank node identifiers.  Blank nodes
should
>>>>>>>>>>>>>> >>>>>>>>>>always
>>>>>>>>>>>>>> >>>>>>>>>>be
>>>>>>>>>>>>>> >>>>>>>>>> identifiable by the triples they appear in so it
should be
>>>>>>>>>>>>>> >>>>>>>>>>possible
>>>>>>>>>>>>>> >>>>>>>>>>to
>>>>>>>>>>>>>> >>>>>>>>>> formulate API calls or SPARQL queries that validate
that you
>>>>>>>>>>>>>> >>>>>>>>>>have
>>>>>>>>>>>>>> >>>>>>>>>>produced
>>>>>>>>>>>>>> >>>>>>>>>> the data you expected.
>>>>>>>>>>>>>> >>>>>>>>>>
>>>>>>>>>>>>>>> >>>>>>>>>>>
>>>>>>>>>>>>>>> >>>>>>>>>>>2. There is a bad memory leak in during SPARQL
>>>>>>>>>>>>>>> execution of
>>>>>>>>>>>>>>> >>>>>>>>>>>this:
>>>>>>>>>>>>>> >>>>>>>>>>
>>>>>>>>>>>>>> >>>>>>>>>> Define bad memory leak?
>>>>>>>>>>>>>> >>>>>>>>>>
>>>>>>>>>>>>>> >>>>>>>>>> Updates are transactional so it may be a side effect
of the
>>>>>>>>>>>>>> >>>>>>>>>>library
>>>>>>>>>>>>>> >>>>>>>>>> maintaining the state necessary to rollback the
>>>>>>>>>>>>>> transaction
>>>>>>>>>>>>>> >>>>>>>>>>should
>>>>>>>>>>>>>> >>>>>>>>>>it
>>>>>>>>>>>>>> >>>>>>>>>>fail
>>>>>>>>>>>>>> >>>>>>>>>> or be aborted.  Also the fact that you are replacing
constant
>>>>>>>>>>>>>> >>>>>>>>>>nodes
>>>>>>>>>>>>>> >>>>>>>>>>with
>>>>>>>>>>>>>> >>>>>>>>>> blank nodes will assign a lot of new identifiers and
those
>>>>>>>>>>>>>> >>>>>>>>>>identifiers
>>>>>>>>>>>>>> >>>>>>>>>> have to be tracked to prevent collisions.
>>>>>>>>>>>>>> >>>>>>>>>>
>>>>>>>>>>>>>>> >>>>>>>>>>>
>>>>>>>>>>>>>>> >>>>>>>>>>>PREFIX rr: <http://www.w3.org/ns/r2rml#>
>>>>>>>>>>>>>>> >>>>>>>>>>>DELETE { ?map rr:graph ?value . }
>>>>>>>>>>>>>>> >>>>>>>>>>>INSERT { ?map rr:graphMap [ rr:constant ?value ] . }
>>>>>>>>>>>>>>> >>>>>>>>>>>WHERE { ?map rr:graph ?value } ;
>>>>>>>>>>>>>>> >>>>>>>>>>>
>>>>>>>>>>>>>>> >>>>>>>>>>>DELETE { ?map rr:object ?value . }
>>>>>>>>>>>>>>> >>>>>>>>>>>INSERT { ?map rr:objectMap [ rr:constant ?value ] . }
>>>>>>>>>>>>>>> >>>>>>>>>>>WHERE { ?map rr:object ?value } ;
>>>>>>>>>>>>>>> >>>>>>>>>>>
>>>>>>>>>>>>>>> >>>>>>>>>>>DELETE { ?map rr:predicate ?value . }
>>>>>>>>>>>>>>> >>>>>>>>>>>INSERT { ?map rr:predicateMap [ rr:constant ?value ]
. }
>>>>>>>>>>>>>>> >>>>>>>>>>>WHERE { ?map rr:predicate ?value } ;
>>>>>>>>>>>>>>> >>>>>>>>>>>
>>>>>>>>>>>>>>> >>>>>>>>>>>DELETE { ?map rr:subject ?value . }
>>>>>>>>>>>>>>> >>>>>>>>>>>INSERT { ?map rr:subjectMap [ rr:constant ?value ] .
}
>>>>>>>>>>>>>>> >>>>>>>>>>>WHERE { ?map rr:subject ?value }
>>>>>>>>>>>>>>> >>>>>>>>>>>
>>>>>>>>>>>>>>> >>>>>>>>>>>The full code is simply:
>>>>>>>>>>>>>>> >>>>>>>>>>>
>>>>>>>>>>>>>>> >>>>>>>>>>>var dataset = new InMemoryDataset(store,
>>>>>>>>>>>>>>> R2RMLMappings.BaseUri);
>>>>>>>>>>>>>>> >>>>>>>>>>>            ISparqlUpdateProcessor processor = new
>>>>>>>>>>>>>>> >>>>>>>>>>>LeviathanUpdateProcessor(dataset);
>>>>>>>>>>>>>>> >>>>>>>>>>>            var updateParser = new
>>>>>>>>>>>>>>> SparqlUpdateParser();
>>>>>>>>>>>>>>> >>>>>>>>>>>
>>>>>>>>>>>>>>> >>>>>>>>>>>
>>>>>>>>>>>>>>> 
>>>>>>>>>>>processor.ProcessCommandSet(updateParser.ParseFromStr>>>>>>>>>>>>>>>
ing(Shortcu
>>>>>>>>>>>>>>> >>>>>>>>>>>tS
>>>>>>>>>>>>>>> >>>>>>>>>>>ub
>>>>>>>>>>>>>>> >>>>>>>>>>>m
>>>>>>>>>>>>>>> >>>>>>>>>>>a
>>>>>>>>>>>>>>> >>>>>>>>>>>p
>>>>>>>>>>>>>>> >>>>>>>>>>>sRe
>>>>>>>>>>>>>>> >>>>>>>>>>>placeSparql));
>>>>>>>>>>>>>>> >>>>>>>>>>>
>>>>>>>>>>>>>>> >>>>>>>>>>>Is this a know problem and has been already fixed or
should I
>>>>>>>>>>>>>>> >>>>>>>>>>>investigate closely?
>>>>>>>>>>>>>> >>>>>>>>>>
>>>>>>>>>>>>>> >>>>>>>>>> This is not a known issue, I would also guess that the
data
>>>>>>>>>>>>>> >>>>>>>>>>being
>>>>>>>>>>>>>> >>>>>>>>>>used
>>>>>>>>>>>>>> >>>>>>>>>> would have some bearing on the severity of the
>>>>>>>>>>>>>> problem.  Please
>>>>>>>>>>>>>> >>>>>>>>>>go
>>>>>>>>>>>>>> >>>>>>>>>>ahead
>>>>>>>>>>>>>> >>>>>>>>>> and investigate but I would suspect it is the two
things I
>>>>>>>>>>>>>> >>>>>>>>>>outlined
>>>>>>>>>>>>>> >>>>>>>>>>above
>>>>>>>>>>>>>> >>>>>>>>>> which are the culprits here.
>>>>>>>>>>>>>> >>>>>>>>>>
>>>>>>>>>>>>>> >>>>>>>>>> Rob
>>>>>>>>>>>>>> >>>>>>>>>>
>>>>>>>>>>>>>>> >>>>>>>>>>>
>>>>>>>>>>>>>>> >>>>>>>>>>>Thanks,
>>>>>>>>>>>>>>> >>>>>>>>>>>Tom
>>>>>>>>>>>>>>> >>>>>>>>>>>
>>>>>>>>>>>>>>> 
>>>>>>>>>>>----------------------------------------------------->>>>>>>>>>>>>>>
-----------
>>>>>>>>>>>>>>> >>>>>>>>>>>--
>>>>>>>>>>>>>>> >>>>>>>>>>>--
>>>>>>>>>>>>>>> >>>>>>>>>>>-
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>>>>>>>>>>>>>>> >>>>>>>>>>>_______________________________________________
>>>>>>>>>>>>>>> >>>>>>>>>>>dotNetRDF-bugs mailing list
>>>>>>>>>>>>>>> >>>>>>>>>>>dot...@li...
>>>>>>>>>>>>>>> 
>>>>>>>>>>>https://lists.sourceforge.net/lists/listinfo/dotnetrdf-bugs
>>>>>>>>>>>>>> >>>>>>>>>>
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>>>>>>>>>>>>>> >>>>>>>>>> _______________________________________________
>>>>>>>>>>>>>> >>>>>>>>>> dotNetRDF-bugs mailing list
>>>>>>>>>>>>>> >>>>>>>>>> dot...@li...
>>>>>>>>>>>>>> >>>>>>>>>>
>>>>>>>>>>>>>> https://lists.sourceforge.net/lists/listinfo/dotnetrdf-bugs
>>>>>>>>>>>> >>>>>>>>
>>>>>>>>>>>> 
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>>>>>>>>>>> >>>>>>>
>>>>>>>>>>> >>>>>>>
>>>>>>>>>>> >>>>>>>
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>>>>>>>>>>> >>>>>>>_______________________________________________
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>>>>>>>>>> >>>>>>
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>>>>>>>>>> >>>>>>
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>>>>>>>>> >>>>>
>>>>>>>>> >>>>>
>>>>>>>>> >>>>>
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>>>>>>>>> >>>>>_______________________________________________
>>>>>>>>> >>>>>dotNetRDF-bugs mailing list
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>>>>>>>> >>>>
>>>>>>>> >>>>
>>>>>>>> >>>>
>>>>>>>> >>>>
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>>>>>>>> >>>>account!
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>>>>>>>> >>>> _______________________________________________
>>>>>>>> >>>> dotNetRDF-bugs mailing list
>>>>>>>> >>>> dot...@li...
>>>>>>>> >>>> https://lists.sourceforge.net/lists/listinfo/dotnetrdf-bugs
>>>>>>> >>>
>>>>>>> 
>>>--------------------------------------------------------------------->>>>>>>
---
>>>>>>> >>>--
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>>>>>>> account!
>>>>>>> >>>http://www2.precog.com/precogplatform/slashdotnewsletter
>>>>>>> >>>_______________________________________________
>>>>>>> >>>dotNetRDF-bugs mailing list
>>>>>>> >>>dot...@li...
>>>>>>> >>>https://lists.sourceforge.net/lists/listinfo/dotnetrdf-bugs
>>>>>> >>
>>>>>> >>
>>>>>> >>
>>>>>> >>
>>>>>> >>
>>>>>> >>
>>>>>> 
>>----------------------------------------------------------------------->>>>>>
--
>>>>>> >>-----
>>>>>> >> Precog is a next-generation analytics platform capable of advanced
>>>>>> >> analytics on semi-structured data. The platform includes APIs for
>>>>>> >>building
>>>>>> >> apps and a phenomenal toolset for data science. Developers can use
>>>>>> >> our toolset for easy data analysis & visualization. Get a free
>>>>>> account!
>>>>>> >> http://www2.precog.com/precogplatform/slashdotnewsletter
>>>>>> >> _______________________________________________
>>>>>> >> dotNetRDF-bugs mailing list
>>>>>> >> dot...@li...
>>>>>> >> https://lists.sourceforge.net/lists/listinfo/dotnetrdf-bugs
>>>>> >
>>>>> 
>------------------------------------------------------------------------->>>>>
-
>>>>> >----
>>>>> >Precog is a next-generation analytics platform capable of advanced
>>>>> >analytics on semi-structured data. The platform includes APIs for
>>>>> building
>>>>> >apps and a phenomenal toolset for data science. Developers can use
>>>>> >our toolset for easy data analysis & visualization. Get a free account!
>>>>> >http://www2.precog.com/precogplatform/slashdotnewsletter
>>>>> >_______________________________________________
>>>>> >dotNetRDF-bugs mailing list
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>>>>> >https://lists.sourceforge.net/lists/listinfo/dotnetrdf-bugs
>>>> 
>>>> 
>>>> 
>>>> 
>>>> 
>>>> ---------------------------------------------------------------------------
>>>> ---
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>>>> analytics on semi-structured data. The platform includes APIs for building
>>>> apps and a phenomenal toolset for data science. Developers can use
>>>> our toolset for easy data analysis & visualization. Get a free account!
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>>>> https://lists.sourceforge.net/lists/listinfo/dotnetrdf-bugs
>>> ----------------------------------------------------------------------------
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>>> analytics on semi-structured data. The platform includes APIs for building
>>> apps and a phenomenal toolset for data science. Developers can use our
>>> toolset for easy data analysis & visualization. Get a free account!
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>> - Precog is a next-generation analytics platform capable of advanced
>> analytics on semi-structured data. The platform includes APIs for building
>> apps and a phenomenal toolset for data science. Developers can use our
>> toolset for easy data analysis & visualization. Get a free account!
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> ------------------------------------------------------------------------------
> Precog is a next-generation analytics platform capable of advanced analytics
> on semi-structured data. The platform includes APIs for building apps and a
> phenomenal toolset for data science. Developers can use our toolset for easy
> data analysis & visualization. Get a free account!
> http://www2.precog.com/precogplatform/slashdotnewsletter______________________
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