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1500 questions
42
votes
18 answers
Why do you use ArcGIS for Desktop?
I'm new to GIS, having only dabbled with ArcGIS for Desktop for about 4 weeks in 2007. The business I am at wants to target writing complete solutions that involve GIS as it would benefit their hardware sales. They do not know which market they want…
JonWillis
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42
votes
6 answers
How to get raster corner coordinates using Python GDAL bindings?
Is there a way to get the corner coordinates (in degrees lat/long) from a raster file using gdal's Python bindings?
A few searches online have convinced me that there is not, so I have developed a work around by parsing the gdalinfo output, it's…
EddyTheB
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42
votes
8 answers
Interrupting contour lines beneath elevation labels (instead of using label buffers) using QGIS?
Is there a way to interrupt a contour line beneath an elevation label using QGIS?
MartinMap
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- 114
42
votes
5 answers
Fixing non-noded intersection problem using PostGIS
I'm using a PL/R function and PostGIS to generate voronoi polygons around a set of points. The function that I am using is defined here. When I use this function on a particular dataset I get the following error message:
Error : ERROR: R…
djq
- 16,297
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42
votes
5 answers
Visualizing large datasets with other than Leaflet
When using Leaflet to visualize a large dataset (GeoJSON with 10,000 point features), not surprisingly the browser crashes or hangs. A sub-sample of 1000 features from the same dataset works flawlessly. Unfortunately, I can't share the dataset for…
Imad
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42
votes
1 answer
Is WGS84 itself a Coordinate Reference System?
I was wondering the difference between WGS84 and EPSG:4326 (see this).
Can then WGS84 on its own be defined as a Coordinate Reference System?
Or is it just a datum so that a Coordinate System must be attached to it to fully define a CRS? (see e.g.…
Campa
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42
votes
12 answers
Tablet or smart phone GPS vs "real" GPS
I've been reading a lot today about android and iphone devices being used for spatial data collection in the field and it sure seems to be that single purpose devices such as the extremely popular Garmin eTrex are a dead end. Why buy something with…
matt wilkie
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42
votes
1 answer
Coordinate system for accurately calculating areas of polygons that cross UTM Zones?
I have multiple polygons, all located offshore around the UK. I am trying to calculate the areas of these polygons in square kilometres, without splitting them by UTM zone.
Is it possible to do this accurately? I have been using World Mercator, but…
the_bonze
- 817
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42
votes
5 answers
Generating equal sized polygons along line with PyQGIS
I would like to create polygons along a line to use them for AtlasCreator in a next step.
ArcMap has a tool called Strip Map Index Features.
With this tool I can choose the height and width of my polygons (say 8km x 4km) and produce/rotate them…
Berlinmapper
- 525
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- 10
41
votes
15 answers
Using Computer Games to display GIS data?
Besides being a GIS user I'm a big computer game fan.
Games like Civilization, Minecraft, World at War and many others have a very powerful engine to display huge maps in a beautiful way.
Is it possible to use a game engine to display GIS data…
Pablo
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41
votes
6 answers
Drawing lines from points in QGIS
I have a point layer and need to draw a line passing through or in the vicinity of the points (up to 0.5m distance between the point and the line).
The nodes of the line will receive the attributes of the points closest to them.
H.Wiener
- 1,009
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41
votes
6 answers
Shapefile PRJ to PostGIS SRID lookup table?
I was wondering if there is such a thing as an shapefile PRJ to PostGIS SRID lookup table? Something that can translate the most standard shapefile PRJ definitions into the likely SRID.
When using PostGIS and pgAdminIII, if you use the postgisgui…
RyanKDalton
- 23,068
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41
votes
4 answers
Loading OpenStreetMap data in QGIS?
In QGIS 1.8 I used the openstreetmap plugin to request data from the server, or open a .osm XML file, which produced 3 layers (polygons, polylines and points) in QGIS.
This was great (give or take the 64bit bug which highly affects the freshly…
Laurent S
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41
votes
5 answers
Making beautiful maps in R?
There are quite some nice possibilities to analyse spatial data in R and in the context of my current project I would like to use R more frequently to do that.
Until now I plot my maps with ggplot2 package that brings a lot of practical tools to…
Dspanes
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41
votes
12 answers
How would I draw and visualize custom maps based on OSM data?
I would like to be able to use openstreetmap data for a specific region as a source and "draw" from that the map of infrastructure improvements - mostly roads.
I want it to be self-hosted (not spoiling any data on the real OSM servers), want to…
arconaut
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