The OGR Simple Features Library is a C++ open source library (and command line tools) providing access to vector file formats.

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GDAL/OGR to extract pixel values

I want to use GDAL/OGR to extract pixel values from a raster file. The extraction should be based on polygons, stored in a shapefile. My thought was to iterate over the features in the shapefile, ...
2
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2answers
812 views

Export from PostGIS to SpatiaLite?

My PostGIS database contains OSM data from my country. For transportation reasons I want to export a spatial view I created from that data to a SpatiaLite database. Is there any way to directly ...
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1answer
126 views

Importation of .csv on grass gis converts numeric data to string data

When importing a csv file on grass7, the numeric data is converted into a data of type string. My csv looks like this : id_core value 1 F1 83.0611472396 2 F2 98.8584345936 3 F3 ...
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1answer
253 views

How to detect a GDAL/OGR 'Warning'?

When I run a batch script using a GDAL/OGR program, I can detect if an error occured by checking ERRORLEVEL for the value 1. When using GDAL/OGR in python or .NET, I get an exception when an error ...
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1answer
184 views

Why won't OGR connect to my PostGIS database, but QGIS will?

Trying to connect to my PostGIS database with some success... One hiccup is that OGR will not connect to my server from a remote machine, though QGIS can connect to it just fine from that same ...
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1answer
826 views

ogr2ogr coverting DXF to shapefile, why am I losing part of the feature?

I'm starting to mess around with some of the GDAL toolsets, specifically the ogr2ogr. I'm working with converting a 2000 ACSII DXF file to shapefiles depending on geometry. Everything seems to work ...
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0answers
126 views

How to shift vertices of shapes in shapefile using FOSS python library?

I need to shift each vertice of shape in a shapefile (of any type:point, line, polygon, multiline etc.) with Python. I need to loop in all shapes, get the vertices, get it's coordinates and for each ...
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1answer
100 views

Using ogrinfo to list all projection source of a database [closed]

I have to reproject all the layers from a database, but some of them are undefined and some are defined in a wrong projection. I would like to sort all those layers in a text file with their source ...
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1answer
87 views

ogr SetAttributeFilter uppercase?

How do I use the ogr SetAttributeFilter with uppercases? Code example: lyr = shp_obj.GetLayer() sel_str = "%s = '%s'" % (field, value) lyr.SetAttributeFilter(sel_str) Can I just do: sel_str = ...
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2answers
135 views

Erase method using ogr

I'm trying to find the erase geoprocessing method as i am familiar with in ARC, but i can't seem to find it in OGR using Python. I have looked through the module ogr documentation but perhaps i missed ...
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1answer
323 views

How do I get the centroid of line with OGR

Can somebody explain how to get the centroid of a feature with ogr? I have no idea what the centroid() function itself does. >>> linelyr = lineshp.GetLayer() >>> f = ...
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1answer
202 views

SetGeometry problems when using python/ogr

So i am trying to use the difference function and i pretty much create the new file i want but the Geometry is empty. No error is produced. any help would great! Thanks. #!/usr/bin/env python import ...
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1answer
93 views

Is there a quicker way of checking if a feature exists with OGR

I'm writing lot's of features to a FileGDB using OGR. The slow point in my script is checking that the feature isn't already in the Feature Class, based on the ID. Currently I'm using a function ...
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1answer
74 views

Is georeference the same as geotransform?

Does georeference mean the same as geotransform? If not then what is the difference?
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1answer
234 views

Geometry Projection Speed Test

Lately I've been using the OGR projection classes that come with ogr/gdal, but pyproj was recommended to me, so I thought I'd give it a try. To help me decide if I should make the switch, I did a ...
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2answers
417 views

Python GDAL/OGR: retrieved feature is NoneType

I'm doing some scripts in Python to deal with shapefiles, and I have an issue I don't understand. I'm looping over a shapefile, and I want to retrieve the geometry of each feature, but very often I ...
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1answer
271 views

OGR Info - Check for spatial index?

If we want to get information about a vector layer (shapefile for example) we could use ogrinfo: ogrinfo -so myshapefile.shp mylayer This returns a lot of pertinent information about the shapefile. ...
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4answers
370 views

How to computational efficiently check if there are any overlapping polygons in a group of polygons?

I need to do some processing with groups of polygons. If any of the polygons in the group overlaps other polygon the result is unpredictable and don't throw any error. So, I need to detect if there is ...
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0answers
88 views

Gdal/Ogr - OGRLayer.Intersection() Question

I was trying to perform intersection on two feature classes (shape file format) using OGRLayer.Intersection(), but have problems making it work with C# bindings. I am not able to figure out on how to ...
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274 views

ogr.GetDriverByName('FileGDB') returns None

I installed: gdal-110-1600-x64-core.msi GDAL-1.10.0.win-amd64-py2.7.msi gdal-110-1600-x64-filegdb.msi from www.gisinternals.com I can open my gdb on the command line: C:\data>ogrinfo ...
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0answers
71 views

Confusing offsets in shapefile written by QGIS/OGR

I think I'm stuck here. A shapefile has been updated in QGIS. Records have been deleted and those records have been marked with an asterix in the first byte of the record in the dbf file. I open the ...
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2answers
507 views

OGR Projection transformation error

I am trying to convert shapefile that was created by FME in EPSG:900913 to EPSG:3857 (I know its the same definition) with OGR in a script. datasource = ogr.Open(os.path.join(dirname,shapefileName)) ...
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1answer
165 views

How to sort features in a layer using OGR/Python?

How can I sort the features of an ogr layer by the values of a field? I tried naive variations of def sortlayer(ds, layer, field): lname = layer.GetName() lsort = ds.ExecuteSQL(b'select * ...
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1answer
1k views

Installing GDAL with Java Bindings (gdal.jar) on Ubuntu 12.10

I am trying to build a postgis importer for mutliple shapefiles. After geotools took orders of magnitude longer than shp2pgsql to import my data, I decided to attempt to use the java bindings to GDAL ...
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1answer
207 views

How to create feature LineString in a Polygon shape file layer (OGR/GDAL)?

I used below codes to create ShapeFile layer OGRDataSource *poDS, *poSHPDS; OGRLayer *poSHPLayer; ...... poSHPLayer = poSHPDS->CreateLayer (shpFileName, NULL, wkbPolygon , NULL); And I ...
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1answer
229 views

Python - OGR: Distance different than in ArcGIS

I want to determine the shortest distance between a point and a line. I use the following Python script to do so. If I compare the result of the script with the result of ArcMap's Near Analysis, I get ...
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1answer
169 views

Problem with showing Shape file in Geoserver

I have a number of Shape files from a customer. I can read them with both ogrinfo and QGIS. They don't have a prj-file, but I know that the projection is EPSG:3006. When I add them as layers in ...
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116 views

How to check are there any OGRGeometry (polygons) within an OGRGeometry (polygon) ?

Please see my image: I used the below statements to get Geometry: OGRGeometry *poGeometry; poGeometry = poFeature->GetGeometryRef(); Do you know how to check whether the Polygon 1 ...
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1answer
145 views

Can't convert geometry from Dgn file to Shape file?

I am using below codes to try convert geometry from a Dgn file to Shape file. But, I can't exit the Feature reading loop. Are there anyone know why and how to fix it ? Please download the dgn file ...
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1answer
537 views

How to rename field names in a shapefile from the commandline?

I need to rename the field names (attributes) in a shapefile. Is there an easy way to do this from the command line?
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48 views

How do I get the domain from an OGRSpatialReference?

I would like to know what the projected bounds are for a spatial reference using OGRSpatialReference. Is there some way to use the GetProjParm method to get this information? An example of what ...
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1answer
2k views

How do I get the pixel value of a GDAL raster under an OGR point without NumPy?

I am working on a computational model of the abundance of wild pollinators across a landscape. The model itself is complete, and I am now struggling with a post-processing step. I have my GDAL ...
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1answer
715 views

Python - OGR: Transform coordinates from meter to decimal degrees

I have a point in a shapefile. The shapefile is in a WGS_1984_Web_Mercator Projected Coordinate System. I want to get the coordinates of that point in decimal degrees with GDAL/OGR in Python. I am ...
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1answer
127 views

Creating prepared geometries with OGR from Python

Is it possible to create a prepared geometry object using the Python SWIG geos.ogr module? It seems that Shapely and GeoDjango both have this functionality, but I can't see any mention of it in the ...
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0answers
87 views

Python GDAL/OGR: check lines geometries connectivity

I'm working with shapefiles representing roads, so basically it's stored as (poly)lines. I need to perform a road connectivity checking. In other words, I want to ensure that roads meant to ...
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3answers
191 views

How to test if geometry is inside another?

I need to tell whether geometries from a shapefile are inside other geometries or not. For example, I want to test if there are trees (represented as points in trees.shp) inside the urban areas ...
2
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1answer
410 views

Batch convert OSM/PBF data

I need to import some OSM data about a region of Italy into a SHP file or Postgres DB, possibly with batch process. I already use OGR2OGR to batch import data from SHP to Oracle and Postgres and I ...
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1answer
120 views

OGR UnionCascaded gives strange lines (flat polygons)

I'm using OGR to perform a union using UnionCascaded. All my polygons have been created by GDAL polygonize which ensures that all polygons follow pixel edges and should therefore align nicely. But I ...
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4answers
408 views

Get vector features inside a specific extent

The problem: I have a very large vector layer with many features and a much smaller raster layer in a defined region. I want to get only those vector features which are within the raster layers ...
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2answers
2k views

Generating GeoJSON with Python

Hi I want to programatically create a GeoJSON file using polygons from a shapefile but adding attributes from my own application. This is easily done for a shapefile: def ...
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4answers
1k views

Is there a mapping between OGR and python data types?

I'm writing a shapefile using OGR in python, creating fields on-the-fly from a python data source. Creation of a new field requires an OGR data type, is there a mapping between OGR and python data ...
3
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1answer
968 views

better way to duplicate a layer using ogr in python?

I'm splitting a large shapefile into many smaller ones using ogr. I'd like to just copy all of the field and layer config information from the original. Here's how I'm doing it now: src = ...
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2answers
1k views

Is there a way to get at C's OGRLayer.Intersection() or OGRLayer.Clip() in Python?

I am working with OGR in Python and noticed that the C libraries have useful Intersection() and Clip() functions as part of the Layer class. Is there any way to get at these functions in Python? I ...
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0answers
47 views

how to get correct geo reference system for a VMap

I am new to GIS, trying to read the GeoRef System for VMap by using the following code: OGRSpatialReference *ref = layer->GetSpatialRef(); if( ref ) { QString georefSystem = ...
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4answers
6k views

How to add an attribute field to an existing Shapefile via Python

I have a Python script that adds an attribute field to a Shapefile if doesn't exist. This is easy to do with ArcGIS (graphically or via Python), but I'm looking for something that doesn't depend on ...
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101 views

traversing KML files with ogr python

i'm new to OGR processing and KML format so be gentle: i've got a series of KML files all containing multiple regions partitioning a larger area in each. i also have a series of geocoded points for ...
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1answer
253 views

OGR - Weird GeomType -2147483645 on polygon shapefile

I am trying to import a shapefile (multipolygon) in an app with ogr but I got an error about invalid geom type. If I inspect the data with ogr like this: datasource = ogr.Open("c:\\temp\\data.shp") ...
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1answer
406 views

OGR OSM-driver unable to open datasource

I want to read an OSM file with OGR. I use Version GDAL 1.9.1, released 2012/05/15. To read a SQLITE file works fine: $ ogrinfo test.sqlite INFO: Open of `test.sqlite' using driver `SQLite' ...
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1answer
204 views

Convex Quadrilateral Polygons subdivision in equal parts using Python / OGR

Consider an irregular polygon (P) which has four vertices. I would like to subdivide P into smaller polygons as shown here http://i.stack.imgur.com/4SKhB.jpg In the old days I was using ArcGIS 9.3 ...
4
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1answer
357 views

Efficient computation of nearest distance for each point to closest polygon

I'm looking for a more efficient way to compute the nearest distance between features from 2 layers, in this example for each point the nearest distance to the closest polygon. Is there a more ...