[gdal-dev] Zonal statistics with GDAL/StarSpan

[Brent Fraser]

Greg,

  It means the GEOS topology library is having problems with geometry of your input shapefile.  Most likely related to duplicate vertices (or near-duplicate) in a polygon.  Do a Google for "side location conflict".   It would be nice if it spat out the FID of the offending polygon...

Brent 

Greg Ederer wrote:
> Hi Brent,
> 
> Thanks for the example.  Here's what I got:
> 
> Macintosh-4:starspan_tests gregederer$ starspan2 --progress --RID none 
> --vector 
> /Users/gregederer/servers/geoserver_data/data/shapefiles/Admin/afadmn2n.shp  
> --raster rfe_2006_04_pct.tif --stats  results.txt avg
> starspan: --out-prefix: ?
> Type `starspan --help' for help
> 
> I then added a --out-prefix, like so:
> 
> Macintosh-4:starspan_tests gregederer$ starspan2 --progress --RID none 
> --vector 
> /Users/gregederer/servers/geoserver_data/data/shapefiles/Admin/afadmn2n.shp  
> --raster rfe_2006_04_pct.tif --stats  results.txt avg --out-prefix bar
> starspan: --out-type: ?
> Type `starspan --help' for help
> 
> I then added '--out-type table' (I found in the source that valid 
> --out-types are: table, mini_raster_strip, mini_rasters, rasterization):
> 
> Macintosh-4:starspan_tests gregederer$ starspan2 --progress --RID none 
> --vector 
> /Users/gregederer/servers/geoserver_data/data/shapefiles/Admin/afadmn2n.shp  
> --raster rfe_2006_04_pct.tif --stats  results.txt avg --out-prefix bar 
> --out-type table
> Number of features: 550
> starspan_csv:   1: Extracting from rfe_2006_04_pct.tif
>        0% terminate called after throwing an instance of 
> 'geos::util::TopologyException'
>  what():  TopologyException: side location conflict -8.25 23.1536
> Abort trap
> 
> Any idea what the TopologyException indicates?
> 
> Thanks!
> 
> Greg
> 
> Brent Fraser wrote:
>> Greg,
>>
>>  I've used StarSpan to do similar things; in my case I wanted "mode" 
>> not "avg".  Using v1.2.01 (I don't think I made major mods to the 
>> source):
>>
>>     starspan2.exe --progress --RID none --vector boundaries.shp  
>> --raster big.tif --stats  results.txt mode
>>
>> I edited the resulting results.txt text (csv) file and used GDAL's 
>> ogr2ogr to do a join on the shapefile's DBF file based on the FID.
>>
>> Brent Fraser
>>
>>
>> Greg Ederer wrote:
>>> Hello all,
>>>
>>> I'm a GDAL newbie.  I have a shape file containing subnational 
>>> boundaries for Africa.  I have a raster containing rainfall for 
>>> Africa.  I need to pull out the spatial average of rainfall for each 
>>> of the subnational units.
>>>
>>> I think that I might be able to pull this off using StarSpan.  But, 
>>> the docs on the StarSpan wiki do not line up with the current version 
>>> of the program (the changelog mentions that certain command line 
>>> switches have been eliminated, and others added; but it doesn't say 
>>> what the new switches do, or how to use them).  I am digging through 
>>> the StarSpan sources to try to figure out how to use it.
>>>
>>> Does anyone have any suggestions as to how I might get the needed 
>>> data using GDAL (with, or without StarSpan)?
>>>
>>> Thanks!
>>>
>>> Greg
>>>
> 
>