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

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1answer
2k views

Is there a silent installation command without the desktop shortcuts? [closed]

I installed QGIS with Microsoft SCCM 2012 and I want to make a silent install without desktop shortcuts. I managed to do a silent install with / S but I found no s command to delete desktop shortcuts....
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votes
4answers
3k views

What are the advantages either way between GML and Shapefiles?

After a good start many months ago of getting into GIS through QGIS, I had to drop what I was doing and did not touch it for quite some time. I am now able to get back into it and have a need to load ...
4
votes
1answer
2k views

Python 3 support in QGIS?

As python3 is getting standard more and more I wonder wether there is or will be support for python 3 in QGIS?
4
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1answer
3k views

How to display an elevation profile and store the DEM elevation back to the KML line?

When I draw a track in Google Earth, for example along a road, I can right-click it to "Show elevation profile", and it displays a 2D plot of distance vs elevation. However, if I save the KML, the ...
4
votes
1answer
2k views

How to pick the coefficient in Inverse Distance Weighted method?

I'm using QGIS 1.8.0 to interpolate weather data. This is, I have a weather station located in say, A and C. With the Inverted Distance Weighting or Triangular Interpolation methods, I can know/...
4
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1answer
2k views

Qgis - How to change GDAL version

im working on Ubuntu 12.04 server; i noticed this when i installed additional support for ECW format into the GDAL 1.9.1 which worked ok. Then i tried to add ECW files to Qgis but it said they still ...
4
votes
1answer
2k views

Unit of $length in QGis Field Calculator

I'm calculating field of various features in my shapefile using QGis. I'm getting some sample length as 0.134914579766986. I want to know in what unit (eg: meters, km etc) is the above value ?
4
votes
1answer
100 views

Importing LiDAR .txt in QGIS for map conversion

I have LiDAR data in .txt files (1000 to 26000 KB), where 2nd column marks x-coordinates, 3rd col y and 4th col z. 8 485000.16 6508997.48 1.84 66 Last 2 485001.27 6508998.92 1.86 82 Last 2 485001.02 ...
4
votes
2answers
176 views

Clip polygon using buffer

I'm very new to QGIS, so apologies if this is a daft question. I've been trying to resolve my problem for a couple of days and I can't get anywhere. I have searched for similar issues here on SE but ...
4
votes
2answers
1k views

GPS-Plugin and Garmin data

I am an avalanche specialist and I use a GPS Garmin 62 for fieldwork. I for example use waypoints to measure snow depth in avalanches for volume calculations. When I add a waypoint in the garmin ...
4
votes
1answer
731 views

QGIS custom CRS for map of manufacturing shop floor

I'm working on a web app that shows a map of a manufacturing plant's shop floor. I've built it in Inkscape and QGIS, but when I try to load it into Tilemill, I get a CRS error. Specifically, it says:...
4
votes
1answer
604 views

QGIS cannot view raster loaded to PostGIS through raster2pgsql

I tried to load a raster GeoTIFF image to a PostGIS database using "raster2pgsql" following the OpenGeo Suite Manual. The command I used is: C:\>raster2pgsql -s 4283 -I -C -M "C:\Program Files\...
4
votes
5answers
1k views

Elevation correction ASTER GDEM2 (+10m)

My ASTER GDEM2 has a average elevation error of -10m for my area. (I testet it using 90 defferential GPS reference points and compared it with old Topo25, SRTM, and GoogleMaps). I would like to ...
4
votes
2answers
113 views

How to import a Composer Template into QGIS Print Composer?

How can I import a .qpt file into Print Composer (Composer Manager) in QGIS. I've tried saving it in the composer_templates folder but to no avail.
4
votes
2answers
107 views

Easier calculation of a surface using QGIS

I'm looking for an easier way to calculate the surface on QGIS: My project CRS is in Lambert93. Currently, when I'm calculating a surface using QGIS, when the surface seems wrong, I always have to: ...
4
votes
0answers
218 views

How can I properly rename a table in a SpatiaLite DB?

Spatial layers (tables) in SpatiaLite include various supporting objects and metadata, including triggers, indices, and entries in (at minimum) the geometry_columns table. I'm looking for (preferably) ...
4
votes
1answer
966 views

Join attributes by location

I am trying to join multiple records that occupy the same location (polygon centroid) and have tried using the join by location plug-in but have found this does not work for me in this case as I have ...
4
votes
3answers
2k views

Summing attributes intersected by under a radius

Apologies - new user. I am working with QGIS on Mac OS X and with shapefiles downloaded from the US Census Bureau that show population data by state and by county. How do I: select certain points (...
4
votes
1answer
335 views

How to get User and Password of a PostGIS layer from PyQGIS

I wonder if it is possible to get the user and password for a PostGIS database if they are stored in the PostGis connection information. I get the connection information at the moment from the ...
4
votes
1answer
201 views

How to rotate labels by the same angle as the map in the composer?

Does someone know if it is possible to make the labels rotate the same angle as the map in the composer? I'm trying using the expression attribute( $map, rotation) in the data defining placement, but ...
4
votes
1answer
271 views

Is it possible to change the year range of time manager in QGIS?

I have a shapefile with a start and end time field, properly formatted. However my dates range from 1864-1995. When I try to use the shape file with the QGIS time manager plugin I keep getting this ...
4
votes
2answers
1k views

Setting layer visibility in QGIS Python API

Im having a problem toggling the visibility of map layers in pyqgis (2.4). I have a simple interface, just the map canvas, no legend, and basically a radio button that toggles between two raster ...
4
votes
1answer
640 views

QGIS Standalone C++ Application with Qt: “The program has unexpectedly finished”

I'm trying to develop an Standalone Application with Qt and QGIS API. There are several code examples that should work, but they don't. The Problem is that everytime I use "QgsApplication" the ...
4
votes
1answer
348 views

How to connect waypoint pairs and calculate length?

I want to make a path out of points and calculate the distances of each single line. I have a point layer with waypoints of a research vessel. The way points have in the attribute table a date and a ...
4
votes
2answers
372 views

Calculating unique ID value for a field in QGIS using python

I am trying to calculate a unique ID field for a vector layer in qgis, using python. I found some code to calculate attribute values, and tried to increment the value in the expression, but it doesn't ...
4
votes
1answer
439 views

Historical U.S.G.S. Georeferencing

I have downloaded a historical USGS map that is suppose to be a geoPDF. My understanding is that QGIS cannot directly read geoPDF's. I have not had any luck in converting it to a geoTIF in order to ...
4
votes
1answer
1k views

Can QGIS resample Rasters during display?

When I was using ArcGIS a user could resample a raster during the display (I think via layer properties under the display tab). This would smooth the appearance of the raster so it wouldn't appear ...
4
votes
1answer
2k views

How to open or import .sdc files in QGIS?

I have some .SDC files i want to look at but i dont have arcview installed. is it possible? i couldnt even find a software that does sdc to shp conversion. any idea? i am using qgis 1.7.4 on both ...
4
votes
1answer
545 views

How to specify coordinate reference system (CRS) for scalebar that is different to project CRS?

Is it possible to specify a coordinate reference system (CRS) for the scalebar that is different to the project CRS? For example, my project CRS uses geographic coordinates (lat/long), the reason ...
3
votes
1answer
94 views

How to always see all band values with Identify Features of QGIS?

Does anyone know if it is possible to get the Identify Features tool in QGIS to show the band values for all the layers shown in the results window? To clarify, whilst I have several bands "showing" ...
3
votes
4answers
2k views

QGIS locked into fullscreen mode on Ubuntu 12.04

No crash in this case, but I made the mistake of toggling to fullscreen mode on my netbook running Ubuntu 12.04. It's now impossible to escape this "No Menus" view, and it seems to have disabled the ...
3
votes
2answers
116 views

Digital Elevation Model and Shapefile not aligned in openWind

I have a digital elevation model and a shapefile containing point features for the location of wind turbines. These two layers appear to be aligned in QGIS but when I open them in openWind, they are ...
3
votes
2answers
159 views

Method for automatic aggregation of polys with sparse data

I am part of a project on presenting health related data on maps. In order to maximize the analytical usefulness of the data, we wish to divide them into as small areas as possible. However, to ...
3
votes
1answer
932 views

query / filter on attribute tables with external tables joined

i tried to do some queries on joiend table fields ... i've got/found some answers concerning version 1.8 - which result in "use select + export to create a combined dataset" so i just did some tests ...
3
votes
5answers
3k views

How to convert KML with tracks to Shapefiles?

I downloaded a KML track from Google Latitude. The service allows to download the tracked route from the user's profile providing a link such as: https://maps.google.com/locationhistory/b/0/kml?...
3
votes
1answer
1k views

Using Qgis server with Ubuntu 12.04

I realise there had been many posts on this subject but unfortunately I need to post again. I've been banging my head against this all day. I'm trying to get qgis server working with Ubuntu 12.04 ...
3
votes
2answers
172 views

I am unable to draw a shape layer

When I add a new shape layer or want to edit an existing one, nothing is happening. I even don't see the dots where I'm clicking. Maybe the problem is I deleted some layers (by opening the .qgs as a ...
3
votes
1answer
365 views

Performing viewshed analysis with Dutch AHN files in QGIS?

i downloaded the new (dutch hight data) AHN files, and was trying to perform a viewshed analysis at some point near UTRECHT. The plugin (grass plugin) works ok, i tried it before with a dem map. ...
3
votes
1answer
97 views

QGIS Select overlapped feature

I have points that are not equal but the distance between them is so small that it can't be seen even at scale 200k:1. I calculated the distance between these points and add it as attribute. Now I ...
3
votes
1answer
107 views

PyQGIS Error: Cannot Create a QPixmap or Qwidget when no GUI is being used

I am trying to create a standalone script using the code below. I was able to add a shapefile with no errors but when I add map = QgsMapCanvas() after qgs.initQgis() and map.setLayerSet([...
3
votes
1answer
2k views

How to install SciPy for QGIS Standalone [closed]

A number of QGIS plugins require the Python package SciPy to be installed. This package is available using the OSGeo4W package based installer or precompiled for Windows, but is not provided as part ...
3
votes
1answer
1k views

JSON URL won't open in QGIS

When attempting to display the national chargepoint registry from the following URL: http://chargepoints.dft.gov.uk/api/retrieve/registry/format/json The following error returns: http://...
3
votes
1answer
222 views

Create new polygon layer based on areas of varying numbers of stacked polygons

I have several species range maps (as polygons) that overlap/stack. From this, I am trying to identify areas of highest biodiversity. Ideally, I'd like to create a new polygon layer, where 1 part is ...
3
votes
2answers
3k views

Set feature attribute by name via QGIS python api

I try to set feature attributes by attribute name with this code pr = layer.dataProvider() pr.addAttributes([QgsField("test", QVariant.Int)]) layer.updateFields() for feature in layer.getFeatures(): ...
3
votes
0answers
105 views

How to digitize 90 degree angles? [duplicate]

Possible Duplicate: How to create polygons with straight lines and right angles in QGIS? In QGIS 1.8 is there a way to digitize buildings etc. with perfect 90-degree angles, Or, edit a polygon ...
3
votes
1answer
266 views

Clusters of points: Determining the centroid (QGIS)

I've basically got the same issue as this post, but can't find a way to transplant the ArcGIS solution to QGIS. I have household-level geo data for 10 villages spread out across the country. I need ...
3
votes
1answer
67 views

Google Maps / StreetView coverage layer in QGIS

I've come across a useful method for adding Google layers as a raster in QGIS: High resolution, printable alternative to OpenLayers plugin for QGIS? Does anyone know what the serverUrl is for the ...
3
votes
1answer
131 views

Where did Processing Algorithms go?

I have recently installed QGIS 2.8.2 on my Windows 8.1 laptop with the stand alone .exe installer. The processing toolbox is missing the GDAL/OGR, GRASS, QGIS algorithms, Saga and the Orfeo Toolbox ...
3
votes
1answer
3k views

How to export shp to kml?

I already browsed your FAQs, and could not come up with a good answer, I am trying to export shp files to kml to be placed on Google Earth. On a previous version of QGIS it was as simple as right ...
3
votes
1answer
915 views

How to create a x-y scatterplot from attributes in QGIS 2.0?

There are a few old packages that allow the creation of x-y scatter plots from attributes in vector data (Scattergram for 1.7) http://plugins.qgis.org/plugins/scattergrammidentify/ (SPQR for very ...