[geos-devel] 3.1.0rc1

[Sean Gillies]

GEOS 3.1.0rc1 is dumping debugging noise from GEOSUnionCascaded,  
something we should fix.

Dane's shapefile is a bit broken, being a mix of polygons and  
multipolygons. Is that the problem?

Sean

On Jan 28, 2009, at 1:45 PM, Paul Ramsey wrote:

> Well, I'm seeing the same thing, with a bit more information:
>
> aggtest=# select geometrytype(st_union(the_geom)) from tm_world;
> NOTICE:  TopologyException: found non-noded intersection between
> 21.8917 -26.6689, 21.9536 -26.6644 and 21.9536 -26.6644, 21.8917
> -26.6689 21.953 -26.6645
> server closed the connection unexpectedly
> 	This probably means the server terminated abnormally
> 	before or while processing the request.
> The connection to the server was lost. Attempting reset: Failed.
> !> \q
>
> The crash is probably the result of bad null/exception handling on my
> part, but the core problem is that one of the union pairs is failing.
> Basically ST_Union(geom1, geom2) still isn't 100% robust, so if you
> find (or create) a pairing that doesn't work, you're SOL.
>
> There's a hack approach to this which would probably work "better",
> but still not 100%, and that would be to catch the exception when it
> occurs in GEOS, and put the bad pair off to the side everything else
> is done. Then try to union(finalresult, bad1) and union(finalresult,
> bad2) in the hopes that the specific problem of union(bad1, bad2)
> doesn't come up in the union with the finalresult.
>
> I'm going to wrap this data into a MULTIPOLYGON for Hartmut to run,
> which should allow him to extract the bad pairing, which we can then
> give to Martin and see if JTS also dislikes it.
>
> P.
>
> On Wed, Jan 28, 2009 at 11:54 AM, Dane Springmeyer  
> <blake at hailmail.net> wrote:
>> Hi Paul and Hartmut,
>>
>> Sean wisely mentioned I should be careful in testing shapefiles  
>> with invalid
>> polygons, which I definitely forgot to think about since I was  
>> reading in
>> the shapefile directly.
>>
>> Nevertheless with both this original shapefile [1] (that does have  
>> invalid
>> polygons) and a cleaned up version (with the buffer(0) trick) that  
>> I have
>> posted here [2], the below script results in the "should never be  
>> reached"
>> assertion.
>>
>> Perhaps the cleaned up shapefile [2] is still invalid for passing  
>> directly
>> to the cascaded_union,  just let me know how to test further.
>>
>> Cheers,
>>
>> Dane
>>
>>
>> [1] http://thematicmapping.org/downloads/TM_WORLD_BORDERS-0.3.zip
>> [2] http://dbsgeo.com/tmp/test_world_shapefile.zip
>>
>>
>> ### python ###
>>
>> from shapely.ops import cascaded_union
>> from osgeo import ogr
>> from shapely.wkb import loads
>>
>> ds = ogr.Open('tm_world_buffer_zero.shp')
>> state = ds.GetLayer(0)
>> states = []
>> while 1:
>>  f = state.GetNextFeature()
>>  if f is None: break
>>  g = f.geometry()
>>  states.append(loads(g.ExportToWkb()))
>>
>> print len(states) # 246
>>
>> u = cascaded_union(states)
>> [....snip...]
>> cxx type MultiPolygon
>> cxx type Polygon
>> cxx type Polygon
>> cxx type Polygon
>> cxx type Polygon
>> cxx type MultiPolygon
>> cxx type MultiPolygon
>> cxx type MultiPolygon
>> cxx type MultiPolygon
>> Assertion failed: (!"should never be reached"), function itemsTree,  
>> file
>> AbstractSTRtree.cpp, line 358.
>> Abort trap
>>
>>
>>
>>
>>
>>
>>
>> On Jan 28, 2009, at 10:33 AM, Paul Ramsey wrote:
>>
>>> Dane, can you provide the shapefile? I will see if this reproduces  
>>> in
>>> PostGIS and generate a test file for Hartmut if it does.
>>>
>>> P.
>>>
>>> On Tue, Jan 27, 2009 at 9:40 PM, Dane Springmeyer <blake at hailmail.net 
>>> >
>>> wrote:
>>>>
>>>> Hi again,
>>>>
>>>> I just did a bit further testing of the new cascaded union  
>>>> goodness via
>>>> Shapely. See the linked email below:
>>>> http://lists.gispython.org/pipermail/community/2009-January/001960.html
>>>>
>>>> Seems that I reached where a point that 'should never be reached' ?
>>>>
>>>> http://trac.osgeo.org/geos/browser/trunk/source/index/strtree/AbstractSTRtree.cpp#L358
>>>>
>>>> I am new to looking at the geos code, so any pointers to help me  
>>>> test
>>>> more
>>>> would be great.
>>>>
>>>> Thanks!
>>>>
>>>> Dane
>>>>
>>>>
>>>> On Jan 27, 2009, at 9:02 PM, Dane Springmeyer wrote:
>>>>
>>>>> Paul,
>>>>>
>>>>> I tested on mac 10.5 and ubuntu 8.10 and all configure;make and  
>>>>> make
>>>>> installs went perfectly.
>>>>>
>>>>> Just a few compiler warnings that I've pasted here:
>>>>> http://dpaste.com/hold/113736/
>>>>>
>>>>> Dane
>>>>>
>>>>> On Jan 27, 2009, at 10:35 AM, Paul Ramsey wrote:
>>>>>
>>>>>> This is a pre-warning to PSC members to download and test the  
>>>>>> first
>>>>>> 3.1 rc tarball:
>>>>>>
>>>>>> http://download.osgeo.org/geos/geos-3.1.0rc1.tar.bz2
>>>>>>
>>>>>> If I don't hear any howls of dismay over the next 24 hours, I  
>>>>>> will
>>>>>> make a wider announcement for testing.
>>>>>>
>>>>>> Paul
>>>>>> _______________________________________________
>>>>>> geos-devel mailing list
>>>>>> geos-devel at lists.osgeo.org
>>>>>> http://lists.osgeo.org/mailman/listinfo/geos-devel
>>>>>
>>>>> _______________________________________________
>>>>> geos-devel mailing list
>>>>> geos-devel at lists.osgeo.org
>>>>> http://lists.osgeo.org/mailman/listinfo/geos-devel
>>>>
>>>> _______________________________________________
>>>> geos-devel mailing list
>>>> geos-devel at lists.osgeo.org
>>>> http://lists.osgeo.org/mailman/listinfo/geos-devel
>>>>
>>> _______________________________________________
>>> geos-devel mailing list
>>> geos-devel at lists.osgeo.org
>>> http://lists.osgeo.org/mailman/listinfo/geos-devel
>>
>> _______________________________________________
>> geos-devel mailing list
>> geos-devel at lists.osgeo.org
>> http://lists.osgeo.org/mailman/listinfo/geos-devel
>>
> _______________________________________________
> geos-devel mailing list
> geos-devel at lists.osgeo.org
> http://lists.osgeo.org/mailman/listinfo/geos-devel