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1500 questions
17
votes
2 answers
When was Esri File Geodatabase API made available?
When was the Esri File Geodatabase API made available?
This question was originally asked to try and determine when the File Geodatabase API would be made available.
Mapperz
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17
votes
2 answers
How to get the geometry type of an empty PostGIS table?
I have a web application that needs to know the geometry type of a PostGIS table's geom field before inserting rows into it. I use the following query to determine the geometry type of the geom column:
SELECT GeometryType(geom) FROM…
Tanner
- 7,375
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- 109
17
votes
1 answer
ArcGIS Raster Mosaic Dataset and GDAL VRT, when to use?
ArcGIS Desktop has a the Raster Mosaic Dataset, QGIS and friends have Virtual Raster Tables.
A skim of the documentation reveals much similarity. They both create or enable an alternate representation of data that sits somewhere else without having…
matt wilkie
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17
votes
2 answers
How do I get the value of the pixel under the cursor?
Is there a tool or something that will give me the value of the pixel under the cursor? What I've got in mind in something like the eyedropper tool in graphics programs that allows you to interactively sample points in a raster image.
Llaves
- 5,963
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17
votes
1 answer
How to copy the color styling to a color column in a layer's attribute table?
I have a polygon layer in QGIS that I have applied a random color style to each polygon. Under Layer Properties -> Style I selected a Categorized style and then generated a random color ramp. I added a color column to the layer table. Is there a way…
user2956607
- 171
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17
votes
3 answers
Lightsquared GPS controversy: Where is the analysis?
GPS World reports that Lightsquared's network of 40,000 transmitters will interfere with GPS signals.
Initial technical analyses have shown
that the distant, low-powered GPS
signals would receive substantial
interference from high-powered,
…
Kirk Kuykendall
- 25,787
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- 153
17
votes
8 answers
Creating convex hull in ArcGIS Desktop?
I would like to be able to create a convex hull in ArcGIS Desktop 9.x, but I cannot find an appropriate tool.
How does one go about creating one?
I am interested in answers for all license levels: ArcView, ArcEditor and ArcInfo.
Charles Roper
- 1,002
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17
votes
4 answers
Is starting names with numbers a bad data naming convention?
My company uses ArcGIS and has a project and data file naming standards in place and (for the most part) followed. Something that has always bothered me about he naming standards is that it mandates starting all project and data file names with the…
hgil
- 478
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17
votes
2 answers
Ortho Projection produces artifacts
I`m trying to create a sphere-like view using qgis and the "world from space"-projection http://spatialreference.org/ref/sr-org/6980/ (essentialy an ortho-projection). ArcGIS wraps the shapes correctly but QGIS (2.01) produces nasty artifacts.
I…
user1523709
- 171
- 1
- 4
17
votes
3 answers
How to load memory output from QGIS processing?
Many processing algorithms have an option to save output as memory. If ran from toolbox, this works fine, because you can tick the "Open output file after running algorithm" box.
Looking at the source code for QGIS, the code for loading the memory…
user23603
17
votes
5 answers
Dynamically set zoom level based on a bounding box
I have a leaflet map whose size depends on the size of the browser window. I would like the zoom level to be dynamically chosen so that it is as zoomed in as possible while showing the entirety of the bounding box.
Right now, I just have the zoom…
Mike McKay
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- 12
17
votes
5 answers
How is elevation and altitude measured?
According to my watch that claims to measure altitude, as far as I can see it says that in Stockholm Sweden the altitude is 170 meters but can that be right? How exactly can we know that 0 altitude in Bangladeh is the same as 0 altitude in…
Niklas Rosencrantz
- 123
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17
votes
2 answers
Seeking QGIS equivalent to Focal Statistics of ArcGIS Spatial Analyst?
I'm attempting to use QGIS v2.0.1 to accomplish the same tasks that I can do using ArcMap v10.1 and I'm running into some trouble finding equivalent tools. In ArcMap I am using the Focal Statistics (mean) Spatial Analyst tool and I do not know if…
cb26
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17
votes
5 answers
How can I measure area from geographic coordinates?
If I have polygons in geographic coordinates (WGS84), how do I measure the total area each takes on the surface of the earth, taking into account the curvature of the earth?
scw
- 16,391
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- 101
17
votes
2 answers
Leaflet: Container coordinates vs Layer coordinates?
What is the difference between map container coordinates and layer coordinates?
From what I gathered, the map container coordinates are always relative to the map viewport, and while layer coordinates always start out with the same values as the…
Saad Malik
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