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1500 questions
38
votes
10 answers

Open Source Tool capable of reading Esri File Geodatabase (.gdb)?

I have an ESRI File Geodatabase (.gdb) file that I would like to convert to shapefile (or any other non-proprietary format). Are there any Open Source tools to do so?
Darren Cope
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38
votes
9 answers

Can QGIS open KMZ files?

I know I can add KML files once I have unzipped the KMZ files, but is there a way to open KMZ files directly? When I try to open a kmz file on QGIS 1.8.0 on Windows XP, through the all files filter, it does not accept it as a valid format. Am I…
afwatl
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38
votes
2 answers

Fastest way to count the number of features in a feature class?

With the introduction of the Data Access module in arcpy (30x faster search cursors), I want to know if counting features matching sql criteria is faster than the traditional MakeTableView + GetCount methodology?
Michael Markieta
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38
votes
6 answers

Polygons and MultiPolygons should follow the right-hand rule

http://geojsonlint.com/ I get error Polygons and MultiPolygons should follow the right-hand rule I used it for past 3 years without any problem with my old GeoJSON file. Now geojsonlint enforce the right hand rule, how to fix the problem. Updated…
hoogw
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38
votes
4 answers

GeoJSON Styling information

As far as I can see there is nothing in the GeoJSON standard to store styling information, i.e. line colours, thicknesses etc. Am I missing something or is this just something that GeoJSON doesn't deal with?
Mr_Chimp
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38
votes
14 answers

Getting boundary of raster image as polygon in ArcMap

I have a rectangular raster image in ArcMap. How can I produce a polygon which is just the extent of the raster image? That is, I want to have a polygon layer with a single quadrilateral which is the edge of the image. I've tried simply doing a…
robintw
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38
votes
4 answers

Getting polygon areas using GeoPandas

Given a GeoPandas's GeoDataFrame containing a series of polygons, I would like to get the area in km sq of each feature in my list. This is a pretty common problem, and the usual suggested solution in the past has been to use shapely and pyproj…
Aleksey Bilogur
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38
votes
1 answer

Getting TopologyException: Input geom 1 is invalid which is due to self-intersection in R?

The 'TopologyException: Input geom 1 is invalid' self-intersection error which arises from invalid polygon geometries has been widely discussed. However, I haven't found a convenient solution on the web that solely relies on R functionality. For…
fdetsch
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38
votes
21 answers

Connecting to PostGIS database from ArcMap for display and query without ArcSDE?

How can I connect to a PostGIS database from ArcMap using ArcGIS Desktop 9.3 and later? I would like to be able to perform spatially enabled queries and receive the results back (e.g. spatial and non-spatial joins, filtering etc.) rather than just…
fmark
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38
votes
3 answers

Creating transparent hillshade?

I get elegant transparent hillshades via a combination gdal and convert. Compare to grey-based hillshade commonly used, such transparent hillshades are very cool because they can be placed between the map background and other upper layers (roads,…
Hugolpz
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37
votes
11 answers

Performing reverse clip in ArcMap

Is there a way to perform a 'reverse' of the clip function in ArcMap? I am not exactly sure how to explain this so here is a diagram:
Alan Carr
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37
votes
2 answers

Clipping raster in R

I am building a map for the northeastern U.S.A. The map background needs to be either an altitude map or a mean annual temperature map. I have two rasters from Worldclim.org which give me these variables but I need to clip them to the extent of the…
I Del Toro
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37
votes
2 answers

Learning ArcPy?

Where can I start to learn ArcPy?
user15888
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37
votes
6 answers

Converting .shp into .gpx using QGIS

I would like to convert .shp into .gpx. Using GIS, I open my shapefile and I tried to "save as" gpx but it gives an OGR error: creation of field ObjectId failed (OGR error: Field of name 'ObjectId' is not supported in GPX schema. Use…
ePascoal
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37
votes
5 answers

Extract Raster Value into Polygon Attribute

I have Raster Data for a State which has Elevation Data in its pixels. I also have Vector layer which has the 300 divisions of State. what I need is, I want to get the average elevation value of particular division from the raster data using…
Mahesh
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