The OGR Simple Features Library is a C++ open source library (and command line tools) providing access to vector file formats.
12
votes
4answers
4k 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 ...
19
votes
2answers
1k views
Can ESRI's File Geodatabase API be Redistributed?
ESRI's file geodatabase API can now be used with GDAL/OGR - http://www.gdal.org/ogr/drv_filegdb.html however each individual seems to have to login to ESRI and download the API files individually. For ...
4
votes
1answer
1k views
How to resample a batch of rasters using OGR/GDAL?
I'm looking for a function similar to GRASS r.resample. I have a folder full of TIF files and want to reduce their resolution ("scale them down") to reduce file size.
12
votes
5answers
3k views
Generate points that lie inside polygon
I have polygon feature and want to be able to generate points inside it. I need this for one classification task.
Generating random points until one is inside the polygon wouldn't work because it's ...
13
votes
3answers
3k views
What's the easiest way to install GDAL and OGR for Python?
I am developing some code in Python, and I want to use the GDAL/OGR python bindings. What is the minimum I need to install in order to use the GDAL and OGR python bindings?
What is the easiest way to ...
9
votes
3answers
2k views
Divide a complex shape file into a grid
I have a decently detailed shapefile with polygon/multipolygon features (the file is about 500mb). It's actually a shapefile of the entire world, with the features representing coastlines. I need to ...
8
votes
4answers
453 views
How to build a geographic database of GPS logs?
On our aerial wildlife surveys we typically generate dozens of GPX files, and usually convert most of them into shapefiles for display in a GIS application. GPX files are a terrific way of keeping all ...
5
votes
2answers
1k views
GDAL Python bindings not picking up OGR PostgreSQL driver
I have a windows server (Microsoft Windows Server 2003) with:
Python 2.7,
PostgreSQL 9.04-1,
GDAL 1.8.1 (installed from the windows installer
(gdal-18-1500-core.msi) hosted at
...
5
votes
3answers
1k views
Create 3D dxf with OGR
Does anyone know if it's possible to create a 3D dxf with OGR. I would like to assign our contour lines a z value and export them to dxf for some cad work.
PS I know FME can do this, however I would ...
6
votes
5answers
1k views
How to convert line simple features to topological network?
using Gdal/ OGR is there a way to convert a shp, kml, or PostGIS line layer into a network of nodes and segments so it can be used in packages such as networkx?
11
votes
3answers
644 views
ogr2ogr fails to convert GeoJson file > 200MB
As a followup to my previous question (Converting SimpleGeo Places GeoJSON file to shapefile), I am now struggling with what I perceive might be an ogr2ogr "memory" limitation, but I cannot be sure. ...
10
votes
2answers
1k views
How to add custom Feature attributes to ESRI Shapefile with Python?
I am seeking a way to take an existing ESRI Shapefile that has a Feature set of 200 countries. Each country Feature has an attribute of "NAME." My objective is to create a Python script that adds an ...
10
votes
2answers
3k views
Point (of a linestring) within Polygon using ogr and Python
I'm currently working on a project in which I need to build a topological network out of the geometry features I find in shapefiles.
So far using Ben Reilly's open source project I've managed to ...
9
votes
3answers
928 views
getting dxf files out of PostgreSQL
I've successfully loaded a bunch of shapefiles into a PostGIS database. I would like to be able to retrieve specific geometry and layers as dxf files based on SQL queries.
I'm using PostGIS, GDAL, ...
8
votes
6answers
700 views
How do I generate thumbnails images from lots of shapefiles?
A colleague and I recently released an Open Source project called Mapoteca which is a set of Python Scripts that integrates with a GDAL/FWTools installation allowing a full walk-through of directories ...
8
votes
4answers
2k views
installing GEOS, PROJ, GDAL/OGR into a python virtualenv on Mac OS X
I am trying to setup an isolated python virtualenv to work on GIS projects on my Mac OS X. Sounds like I will need to install the GEOS, PROJ, GDAL/OGR from the kyngchaos site here ...
7
votes
2answers
261 views
How to catch PostgreSQL/PostGIS errors in GDAL/OGR Python bindings?
Is it possible to catch PostgreSQL output error messages in OGR after a query has failed?
For example
conn.ExecuteSQL('SELECT * FROM non_existing_table;')
In Postgres this returns an error ...
6
votes
1answer
511 views
Spatial joins in OGR SQL
I have seen that OGR supports it's own form of SQL, I was wondering if it's possible to do spatial joins.
Something like select all objects where one intersects the other. I did have a look around ...
5
votes
2answers
573 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 ...
5
votes
2answers
945 views
Call FWTools (ogr2ogr) from ArcGIS python script
In ArcGIS, I want to use a Python script (and a standard ArcGIS script tool UI) to call functionality from FWTools.
How would I make the call to FWTools? I tried using ...
4
votes
1answer
200 views
ogr2ogr when importing from fgdb and use in python
I want import data from my GDB to PostGIS. It works fine on some datasets (all records -data- is imported or nothing is imported) from a gdb but just doesn't import others. I can't find any ...
2
votes
3answers
386 views
How to merge several GML files into one
I have a folder of GML files that I want to be able to merge to create one GML file that I can then view.
I have tried this using the code described but substuting for GML in this website but to no ...
0
votes
1answer
742 views
Reprojecting from MGRm to WGS84 using open-source tools
I would like to work with some of the Michigan state data (for example, this shapefile of cities ), but it is not in a common projection. However, when I try to reproject the file using ogr2ogr and ...
7
votes
2answers
2k views
How to convert GML Surface to SHP Using OGR?
I have a very large .gml file with multiple layers in it. I would like to export one of these layers to .shp. It is a polygon layer (of lakes). However, I am getting the error:
ERROR 1: ...
5
votes
2answers
1k views
Point-in-polygon using Python and OGR
I want to use OGR in Python to write a simple point-in-polygon test:
def point_in_polygon(point, polygon):
"""
point : [longitude, latitude]
polygon : [(lon1, lat1), (lon2, lat2), ..., ...
4
votes
2answers
411 views
Issues with osgeo - qgis.core and arcpy modules
Is it possible to have the python shell from either qgis or argis to load (import) both qgis.core and arcpy?
I am developing a metadata creation tool and have completed the core functionality using ...
3
votes
1answer
456 views
How do you open shapefiles with ogr2ogr
I'm following along the D3 tutorial, and on this line:
ogr2ogr \
-f GeoJSON \
-where "adm0_a3 IN ('GBR', 'IRL')" \
subunits.json \
ne_10m_admin_0_map_subunits.shp
run into the following ...
3
votes
1answer
340 views
How to programatically populate a shapefile field with polygon areas in OGR?
I'm trying to programatically populate a shp field with polygon areas:
import sys
import ogr
ds = ogr.Open( 'tttttttttt.shp', update = 1 )
if ds is None:
print "Open failed./n"
sys.exit( 1 ...
2
votes
1answer
68 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")
...
2
votes
2answers
160 views
OSR Python testSR.ImportFromEPSG(4326) returns empty spatial reference
This is empty using Python .ImportFromEPSG(4326):
import osr
#this fails:
testSR = osr.SpatialReference()
testSR.ImportFromEPSG(4326)
print testSR.ExportToPrettyWkt()
#why did the import from EPSG ...
1
vote
1answer
407 views
Errors when converting MapInfo .tab to .dxf
I am trying to convert some MapInfo files to .dxf format using OGR2OGR using the following command:
OGR2OGR -f "DXF" "input.dxf" "output.TAB" -overwrite -skiperrors
When I run this I am getting a ...
1
vote
2answers
868 views
ogr2ogr srs options: where is the well known definition determined?
In the ogr2ogr documentation it says that when using -a_srs srs_def:
Srs_def can be a full WKT definition (hard to escape properly), or a well known definition (ie. EPSG:4326) or a file with a WKT ...
