[gdal-dev] Re: Editing attributes with ogr causing corrupt shapefile

[Chaitanya kumar CH]

Tom,

The -skipfailures flag skips only failures to create new features. Null
geometries in non-null shapetype shapefile are not handled.
The only way I can think of to clean such a file is by checking the geometry
in each feature.

On Thu, Aug 5, 2010 at 1:01 AM, Tom Jeffery <tjeffery at gmail.com> wrote:

>
> Chaitanya,
>
> I've found the issue with the particular shapefile I'm using.  It actually
> has some null geometries in it, which are fixable using ESRI's "Repair
> Geometry" tool.  I read that ogr2ogr is also suppose to remove records with
> empty geometries, but it doesn't seem to be working on my file, even with
> the -skipfailures flag set.
>
> Any thoughts?  Or is there another good way to clean a shapefile that might
> have null geometries?
>
> Thanks so much for your help so far!
>
> -Tom
>
>
> Chaitanya kumar CH wrote:
> >
> > Tom,
> >
> > GDAL/OGR updates the shapefile along with the dbf file when a feature is
> > changed. That means updating the extents according to the geometries in
> > the
> > changed features. My guess is that there is a problem reading a feature's
> > geometry extents.
> >
> > Call the OGRGeometry::getEnvelope method on each geometry and check if
> the
> > OGREnvelope::MinX and OGREnvelope::MinY values are within the expected
> > extents. You can isolate the problem this way.
> >
> > Otherwise, put together a sample dataset and create a new ticket at
> > http://trac.osgeo.org/gdal/newticket
> >
> > On Wed, Aug 4, 2010 at 10:00 PM, Tom Jeffery <tjeffery at gmail.com> wrote:
> >
> >>
> >> Chaitanya,
> >>
> >> The updated file is read properly with ogrinfo.  The only difference
> >> between
> >> ogrinfo -al between the two, besides the new field that was created, is
> >> the
> >> extent, which looks like this:
> >>
> >> Original file:
> >> Extent: (1528126.013001, 45899.818172) - (1542444.478012, 61468.662925)
> >>
> >> Updated file:
> >>
> >>
> (-179769313486231570000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000.000000,
> >>
> >>
> -179769313486231570000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000.000000)
> >> - (1542444.478012, 61468.662925)
> >>
> >> That...is a really large negative number!  Any idea why it might be
> >> getting
> >> blown up?
> >> -Tom
> >>
> >>
> >> Chaitanya kumar CH wrote:
> >> >
> >> > Tom,
> >> >
> >> > Can you check the destination shapefile with 'ogrinfo' and see if it
> >> > works?
> >> > If ogrinfo gives a valid output of the new file, check with 'ogrinfo
> >> -al'
> >> > and compare it with the old file's output.
> >> > ( http://www.gdal.org/ogrinfo.html )
> >> >
> >> > --
> >> > Best regards,
> >> > Chaitanya kumar CH.
> >> > /tʃaɪθənjə/ /kʊmɑr/
> >> > +91-9494447584
> >> > 17.2416N 80.1426E
> >> >
> >> > _______________________________________________
> >> > gdal-dev mailing list
> >> > gdal-dev at lists.osgeo.org
> >> > http://lists.osgeo.org/mailman/listinfo/gdal-dev
> >> >
> >>
> >> --
> >> View this message in context:
> >>
> http://osgeo-org.1803224.n2.nabble.com/gdal-dev-Editing-attributes-with-ogr-causing-corrupt-shapefile-tp5372483p5373236.html
> >> Sent from the GDAL - Dev mailing list archive at Nabble.com.
> >> _______________________________________________
> >> gdal-dev mailing list
> >> gdal-dev at lists.osgeo.org
> >> http://lists.osgeo.org/mailman/listinfo/gdal-dev
> >>
> >
> >
> >
> > --
> > Best regards,
> > Chaitanya kumar CH.
> > /tʃaɪθənjə/ /kʊmɑr/
> > +91-9494447584
> > 17.2416N 80.1426E
> >
> > _______________________________________________
> > gdal-dev mailing list
> > gdal-dev at lists.osgeo.org
> > http://lists.osgeo.org/mailman/listinfo/gdal-dev
> >
>
> --
> View this message in context:
> http://osgeo-org.1803224.n2.nabble.com/gdal-dev-Editing-attributes-with-ogr-causing-corrupt-shapefile-tp5372483p5373963.html
> Sent from the GDAL - Dev mailing list archive at Nabble.com.
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>



-- 
Best regards,
Chaitanya kumar CH.
/tʃaɪθənjə/ /kʊmɑr/
+91-9494447584
17.2416N 80.1426E
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