Hi Frank Check out this link [1]. It is the online reference on a Utah University course called 'Geoprocessing with Python using Open Source GIS'. It uses GDAL/OGR and is great as a starting point. It has helped me plenty ;)
[1] - http://www.gis.usu.edu/~chrisg/python/ On Tue, Dec 14, 2010 at 8:40 AM, Ari Jolma <[email protected]> wrote: > Frank, > > A FeatureDefn is typically shared by all features in a layer and you need > one to create a feature object. Feature class has SetField and GetField > methods for storing and retrieving the attributes of a feature. > > I hope this helps, > > Ari > > On 12/14/2010 09:33 AM, Frank Broniewski wrote: >> >> Hello, >> >> I have a question concerning OGR's metadata or attribute management when >> converting between geodata vector formats. My question is maybe only loosely >> related to OGR and aims at the internal management of attribute data. >> >> From what I have read and understood from the documentation, OGR uses the >> OGC Simple Feature Specifiaction to transform data from one format to >> another. While reading the OGC specs I could not find a notion on how one >> should deal with attribute metadata, the whole spec seems to be about vector >> geometries only. >> >> Why I ask this: I am a Python user using the ogr python bindings and now >> the need arose that I need to write a flexible geo format exchange software. >> I chose OGR as a base for doing the conversion. My data often comes from >> databases with non standard data and geoemtry formats. So I want to align >> with OGR's internal used Simple Feature Data format, but I don't know >> how/where I should put the attributes / metadata. I see that the Feature is >> the part I have to look at because it has the geometry and the FeatureDfn. >> Unfortunately this is the part I don't understand :-) >> I need to create a FeatureDfn for my Feature which is basically the column >> names and data types? Where do I put my attribute values then? I looked at >> the OGRFeatureDefn Class Reference, but my understanding of OGR is too low >> to understand how this relates to the OGRFeature. >> >> So basically I am looking for a starter tip that pushes me into the right >> direction. Is there some python tutorial somewhere which I missed or >> somebody has a code snippet for me? >> >> Or would it be easier to use internally a format like geojson and use this >> as a starter for converting to other formats? Can OGR always transfer the >> attributes of my geospatial data to other formats? >> >> I am sorry that my question is somewhat unclear, but I have some >> difficulties to find the right form for my question. But I hope that I could >> state my problem in an understandable way :-) >> >> Many thanks for any tipps >> >> Frank >> _______________________________________________ >> gdal-dev mailing list >> [email protected] >> http://lists.osgeo.org/mailman/listinfo/gdal-dev > > _______________________________________________ > gdal-dev mailing list > [email protected] > http://lists.osgeo.org/mailman/listinfo/gdal-dev > -- ___________________________ ___ __ Ricardo Garcia Silva _______________________________________________ gdal-dev mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/gdal-dev
