QGIS is a user-friendly, cross-platform GIS application licensed under the GNU General Public License.

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103 views

Custom python scripts do not appear in SEXTANTE QGIS

Custom python scripts do not appear in Scripts menu in SEXTANTE plugin unless they are either empty or are as simple (and useless) as: ##foo=group ##input=raster OS is openSUSE 12.3; QGIS 1.8 and ...
2
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0answers
60 views

Error importing NOAA’s National Geophysical Data Center as delimited text layer in QGIS version 1.02

I've been struggling with trying to import the most recent data from NOAA’s National Geophysical Data Center earthquake information into Quantum GIS 1.02 for weeks now for a class assignment. I'm ...
0
votes
1answer
953 views

Can not make qgis.db private copy

I've just installed Qgis 2.0.1 and the above error message appears. Does anyone know how to resolve this problem? I think I need to change the permissions of the relevant folder, but I'm not ...
3
votes
2answers
200 views

Can QGIS display individual WMS tiles as it fetches them?

I have a QGIS project accessing a base WMS layer with imagery. How can I tell QGIS to display the individual tiles as it fetches them so that I won't wait for the whole image to load until I see ...
1
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0answers
94 views

Getting an error when I try to import a loaded vector file to the QGIS GRASS Plugin

I am getting an error code when I try to import a contour line vector file GRASS via QGIS. I have been trying to create a DEM from the contour lines following this tutorial: ...
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0answers
151 views

How can I embed IPython into the QGIS console?

I would like to use Ipython in the console to perform tasks more easily. How can I do that? Thanks a lot!
1
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4answers
266 views

How to unpolygonize and remove outermost border?

QGIS has "polygon to line" but this isn't exact reverse engineering of "line to polygon". I want no overlapped border closed lines, just segmented (on each intersected point) lines. Additionally I ...
5
votes
2answers
184 views

Time Manage + Twitter in 2013

I am a geography teacher and would love to map tweets in QGIS for my pupils. I followed all the instructions but it seems Twitter have changed the way they stream their tweets. I can cope with the GIS ...
1
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1answer
225 views

Restricting Tin interpolation in QGIS

I am trying to do a bathymetric map for a lake using QGIS. However, I see no option to impose a mask so interpolation does not extending beyond the boundaries of my lake. I have traced around the ...
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0answers
58 views

Can the software be installed silently?

Can QGIS be silently installed and uninstalled? We are looking to deploy this to several users for evaluation.
2
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0answers
355 views

How to specify cost attributes for network analysis in QGIS using the GRASS plugin?

I have a road dataset with information about the length, speed and drivetime for each segment. I use QGIS 1.9 with the GRASS plugin to do different types of network analysis, but how do I set up the ...
1
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3answers
434 views

Join excel attributes to shape attribute

I am wondering if there is a way to join the attributes from excel tables to shapes in Qgis. I have abbreviations in the shape and want to add the associated complete names from excel file by ...
1
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1answer
84 views

Snap mean coordinate to layer in QGIS and creating MCs for multiple shapefiles

1: I wish to create a mean coordinate for a group of points. However, I would like the new point to be snapped to the nearest point from the set of points used to generate it. How might one go about ...
2
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1answer
1k views

PyQgis question: How to change or set active layer?

Developing a qgis plugin, I found that if no layer is selected in the Layers panel I can iterate over all layers and do anything to them, but "activate" them. Could someone give me a hint please? ...
0
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1answer
126 views

Why does the “Dissolve” tool in QGIS create an empty layer?

I have a shapefile containing cadastral data. I would like to dissolve the polygons using my field "OwnerName". My goal is to get one polygon per landlord's name. When I use the "Dissolve" tool, QGIS ...
4
votes
1answer
382 views

Can Spatialite SQL statements be issued with a python script in QGIS?

In my previous scripting environments (ms-access and Manifold GIS), it was possible to create and execute SQL queries from withing VBA or VB Script procedures. This is really useful for things such ...
1
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1answer
111 views

how can i install Semi-Automatic Classification plugin manually?

I try to install with Fetch Python Plugins. But fetch python plugins show only those which are installed? can i install manually when direct installation failed repeatedly?
4
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2answers
869 views

How to merge TopoJSON features?

I currently have a coordinate based map of the US and it's states for topojson (https://github.com/mbostock/topojson). The coordinates are a JSON array (as topojson works), data looks like this: ...
2
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0answers
89 views

Convert pixel value histogram to table

I am working in QGIS 2.1 with the National Land Cover Database 2006 land cover layer. It is a raster layer with pixel values corresponding to different land cover types. I have clipped this raster to ...
1
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1answer
115 views

Can't get the openlayer plugin to operate [closed]

I can't get the openlayer plugin to run. I've got QGIS V1.8 on Windows 7. I've tried various repo's recommended on different sites; http://plugins.qgis.org/plugins/plugins.xml & ...
3
votes
2answers
186 views

How to determine the location that has the most intersections with other polygons in a certain distance/buffer?

I have a very scattered map with a lot of very differently shaped polygons. Now I want to determine the location where a circle polygon of a certain size intersects the most surface of these scattered ...
2
votes
1answer
68 views

Why does Fetch Python Plugins responded with only the installed ones?

I use QGIS 1.8. Whenever I demand to install plugins through Fetch Python Plugins it displays only those the already installed. I couldn't find for example; point sampling, group stats and photo2shape ...
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2answers
202 views

Intersection between points and polygons in QGis

I have the following problem. I have a shapefile of points and a shapefile of polygons. I want to know WHAT points (not how many) fall inside EACH of the polygons of my multipolygon shp. I thought ...
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2answers
412 views

Deleting points that fall outside a polygon

I have a polygon that is my region of interest. I also have a database of observation points that I have imported into QGIS as a points layer. I'd like to exclude all the observation points that ...
1
vote
1answer
283 views

What's the correct transformation for Lambert Conformal Conic for Mexico?

I have a shp archive without the .prj file. I don´t know the proyection of this shp, but I think it is in lambert conformal conic. Can anybody helpme to proyect this shp? i´ve tried to proyect it in ...
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1answer
231 views

How to install two versions of Qgis on Ubuntu 12.04?

I would like to run multiple versions of QGIS on Ubuntu 12.04. Can I do that, and how if so?
4
votes
2answers
300 views

Best practice in writing automated tests for QGIS plugins

I'm looking for some best practice advice on writing automatic tests for QGIS plugins written in Python. I have written tests for Python scripts in the past using PyUnit (the unittest module), but ...
0
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1answer
126 views

qgis — style edges of layer shapefiles to have thicker borders

I have two layers I'm working with here, both of North Carolina. One is "townships" the other is "counties". I want the counties shapes to have thick edges with no fill-in color. I couldn't find ...
2
votes
2answers
304 views

Can QGIS use a non-spatial Oracle Database?

I'm building my first plugin in qgis, that needs to read some coordinates from an oracle database (not oracle spatial database) and create a shapefile with this points. I'm searching but only find to ...
2
votes
2answers
218 views

How to save colour (color) ramps in QGIS

This strikes me that it should be simple, but efforts in QGIS and research here and elsewhere are not providing a solution. I have a (vector) map which I have to mark out in colours according to the ...
0
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2answers
293 views

How to find and replace all null values in multiple columns?

To find and replace all null values in a specific column I am using: case when "myColumn" is NULL then '99999999' else "myColumn" end But how can I use the QGIS calculator to find and replace all ...
4
votes
0answers
258 views

How do I install Orfeo toolbox and Qgis 1.9?

I'm having a lot of trouble getting Orfeo toolbox and Qgis 2.0 working. I followed the qgis wiki instructios, added the ppa, installed qgis 1.9 (it's beautiful, great work!). But when i tried to ...
2
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1answer
191 views

QGIS Georeferencer, unexpected transformation, and GCP placement

Im trying to get the sample map which i believe to be EPSG:3112 into QGIS and geo referenced. In my screenshot, on the right is the raster in georeferencer with the points i have added. On the left is ...
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1answer
125 views

Can SQLite and SpatialLite files be linked

Coming from a ms-access background, it is common to split up larger applications into several database files. An ms-access database can then access data that is in another database via a linked ...
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2answers
95 views

How can I delete dangling paths after merging features

In my previous question I've asked how to can I merge different polygons while converting to GeoJSON and TopoJSON. After a day of researching I've realized that, rather trying to do it command line, ...
1
vote
2answers
170 views

Integrate grid and polygon of municipalities keeping the biggest municipality per cell with QGIS (or another)

I have a 9x9 grid and a polygon of municipalities of an extensive area of Brazil. My goal is to have a field indicating the biggest municipality per grid cell. I've been trying with intercept without ...
1
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0answers
144 views

Personal Geodatabase not recognized as valid datasource in the last QGIS Windows Weekly build (64 bits)

I was using Personal Geodatabases in QGIS without any problem but it's stopped to work since I installed the last 64 bits weekly build for Windows (1.9.0-35-Setup-x86_64). I'm now receiving an ...
4
votes
2answers
565 views

Reduce the resolution of a shapefile in R (or QGIS if necessary)

I'm using shapefiles of history U.S. state boundaries from NHGIS to make maps in R. These shapefiles are much higher resolution than I need when making maps at the scale of the country: over 2 million ...
0
votes
1answer
114 views

Calculate attribute height of point data

I have an x (easting), y (northing) and z (height) values associated with my point shapefile. I would like to calculate the z values from the DTM I have - how do I do this in QGIS? I am fairly new ...
3
votes
1answer
857 views

How to load a NetCDF-file into QGIS using Python?

I have a CF-conform NetCDF-file which can be loaded into Quantum GIS (Version 1.8) by using the "Add Raster Layer"-button and subsequently choosing the file and the raster layers of interest. This ...
2
votes
1answer
87 views

How to drill down through multiple polygons/points in QGIS?

I have a layer that has multiple polygons sitting on top of each other, is there a way to easily scroll through those polygons that overlap each other? Thanks
3
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2answers
417 views

Which Windows OS is supported?

Please can you tell me which Windows OS Quantum Desktop supports. i.e. Windows 7, XP, Vista etc.
2
votes
1answer
215 views

QGIS Arch Linux compilation error

Just pulled QGIS from git and am trying to compile it, here's the relevant error: [ 89%] Building CXX object python/CMakeFiles/python_module_qgis_core.dir/core/sipcorepart3.cpp.o In file included ...
2
votes
2answers
136 views

How to extract coordinates from a coastline layer?

I have downloaded QGIS and the Natural Earth base maps. I'd like to somehow get a list of coordinates of a selected coastline. I've got the 10m_coastline layer selected to what I want but can't see a ...
0
votes
1answer
91 views

Add image from my computer for background in Print Composer?

Add image either by dropdown or icon does not produce any kind of dialog box where I could upload an image. Item properties is checked and showing in the right hand panel, but it's blank (no options ...
1
vote
1answer
164 views

opening older 9.x Esri .gdb in QGIS?

I want to open an Esri .gdb with QGIS. I have adjusted GDAL and it works fine with an example .gdb provided on another thread on the topic. I still cannot open the .gdb of interest to me and suspect ...
0
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1answer
55 views

How to generate raster from vector in QGIS with resolution matching existing raster?

Is there any way to use open source tools (preferably QGIS) to rasterize a vector to create a raster with the same coordinates and resolution as an existing raster? I know that the map size can be ...
2
votes
2answers
387 views

How can I create a vector layer in PyQGIS from a table without geom column?

In QGIS I've got a Spatialite database containing tables without a geometry column. With the QGIS GUI it is perfectly possible to add such a table as a 'Spatialite vector layer'. But how to do this in ...
1
vote
1answer
346 views

QGIS Shapefiles have the same CRS but dont line up. (Census Tiger Data & State Data)

I have the Census Tiger data for Oregon from http://www.census.gov/geo/maps-data/data/tiger-data.html Then the bottom one of 2010 Census Population & Housing Unit Counts — Blocks. The shp ...
1
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1answer
692 views

Export all visible layers in map view window to DXF (as one)

I'm looking to find a way of exporting all that is visible in the map view window to a dxf file. That is to say, multiple features from multiple layers, all at once. Can this be done?