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

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4
votes
1answer
81 views

Combining 2 different symbologies in QGIS

I've got a layer (road axis) with 2 different attributes : one with the amount of trafic, another with the number of people living next to this road. As symbology for the trafic amount, I like use ...
4
votes
1answer
2k views

Can the units of the measure tool in QGIS be changed?

All, I'm trying to do some error-checking with some rasters I'm creating, and want to measure line distances on the map in feet, rather than meters - which is what the measure line tool seems to be '...
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 ...
3
votes
1answer
470 views

QGIS Join Attributes by Location not working from Python script

I have a shapefile with points, and a shapefile with polygons. I want to sum the attribute value of all points that are within a certain polygon, and I'd like to do this for each polygon in my dataset....
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
239 views

Why do area measurements from “measure area” tool and field calculator differ?

My problem is when using the "measure Area" tool on the toolbar I get the correct value but when using the field calculator in the Layer Attributes the area is very different including -ve areas. ...
3
votes
1answer
638 views

How to make a different font and color of text in labels?

Is it possible to make a bold or italic, and change the color of individual words Label? Example: the first line is bold in red text, font 12, second row 10 green italic font
3
votes
2answers
170 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
51 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
4answers
21k views

Converting shapefiles (.shp) to CAD (.dwg ) format using QGIS?

How to convert shapefiles to .dwg format using QGIS 1.7.0?
3
votes
1answer
247 views

How to achieve better Dissolve results?

I applied the Vector>Geoverarbeitungswerkzeuge>Auflösen (Dissolve) on a zoning plan (see picture zoning plan). I used the attribute village name as the dissolving criteria. The resulting geometry for ...
3
votes
2answers
397 views

Incorrect display of national characters from Spatialite in QGIS, Windows

I used this tutorial by underdark (thanks much :-) ) to convert my area of interest from OSM file (whole Czech Republic downloaded from Geofabrik.de server). Used OSGEO4W shell (saying "GDAL 1.11.0, ...
3
votes
0answers
737 views

Multiple text formats in a qgis label [duplicate]

Is there any way to have multiple text formats in a single qgis label? I am making a map that shows mountain summits. Many of these summits have more than one name and I would like to show each name ...
3
votes
3answers
10k views

Editing a KML file or converting KML to Editable format with attributes

I'm using QGIS. I'm trying to either edit a .kml file someone else created in Google Earth or convert it to another editable format (like a .shp file). I've read the following threads without really ...
3
votes
1answer
3k views

How to get attributes of overlaying polygon layers by a spatial query?

I am new to QGIS and would like to merge selected data/attributes out of the attribute tables from overlaying vector objects on different vector layers without creating new additional layers. Is ...
3
votes
2answers
283 views

Expression for placement of label 'offset from point' by azimuth field using QGIS?

I need help making an expression for labelling points, such that the label is placed in one of the 8 quadrants (above point excluded), based on the azimuth field of the point. For example, if the ...
3
votes
2answers
239 views

How to merge same long lat points with different data into a unique one?

I have a layer where there is more than 1 feature for a same object. Imagine i have a layer called signals. There can be up to 10 features in the same place (long/lat) for a unique signal but the ...
3
votes
1answer
138 views

Referencing Qt UIs external to plugin with python

I'm developing a plugin that sets up a working environment for a user: loading layers (from db), applying styles and several custom designed (Qt) UI files etc. Primary user interaction is in the ...
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
118 views

Is there are way to import non-geo JSON files into QGIS?

Here is a json file containing various attributes relating to countries. However, it does not contain any geographic data. http://bost.ocks.org/mike/nations/nations.json I would like to join these ...
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
374 views

Inverted shading with polygons in QGIS 2.8

Is there a way to modify the style of a poygon .shp file so that everything except the polygon is rendered as shaded? EDIT: see these images if you have trouble understanding. I am going for the ...
3
votes
3answers
2k views

Why can't I open .asc files in QGIS?

Further to my earlier question, I have .nc and .asc files of crop area and production for maize, rice and wheat. It says here, about QGIS importing .asc files: QGIS has native support for this ...
3
votes
3answers
5k views

How to exclude missing values from raster layer?

In my raster layers the value -999 means "missing". Those points completely mess up any colormap in qgis because qgis treats them as normal values and includes them in the classification. I would ...
3
votes
1answer
1k views

How to get custom colormap onto 3D NVIZ in QGIS GRASS

I am trying to create a 3D version of my 2D raster using QGIS GRASS NVIZ. I have been following these steps: http://linfiniti.com/2010/12/3d-visualisation-and-dem-creation-in-qgis-with-the-grass-...
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
1answer
233 views

How do i install QGIS with FileGDB?

Please help me i am very new at this and the last time I asked i was sent to a link about an older version of QGIS. I need to know how to install QGIS 2.0.1 for Windows 8 64 bit so it can recognize ...
3
votes
2answers
1k views

Calculate area in square meters from degrees?

I have a polygon shape file in geographic coordinate system, i would like to calculate area in square meters in QGIS using python. Is there any formula or equation to do this? Thanks
3
votes
2answers
303 views

Understand QGIS errors when importing .csv file

I am trying to import a .csv file as a layer in QGIS and keep getting a number of errors that I don't understand. Is there any documentation of QGIS errors available? Or can you point me towards a ...
3
votes
1answer
1k views

Spatial Join in QGIS 2.2

I am trying to spatially join point layers of some 12,000 women interviewed in Egypt to Egypt's polygon layers (administrative districts boundaries) using QGIS 2.2 and need some advice. I am a QGIS ...
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
1answer
128 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
964 views

Creating a custom attribute table in qgis print composer

is it possible to arrange header and content of an inserted attribute table in qgis print composer? I want to create a custom datasheet with a small map and listed feature information as follows: I ...
3
votes
1answer
223 views

Postgres, loading raster into db and visualize with qgis

I'm trying to import a TIF raster into a Postgres db using this command: Raster2pgsql -s 26591 -I -C -e -Y -F –N -M C:\Users\Ivn\Desktop\Postgre_HOME\scratchmres1.tif -F | psql -U postgres -d ivndb -...
3
votes
8answers
8k views

Exporting to DXF file from QGIS?

Is it possible to export labels based on Shapefile attributes into a DXF file? I use QGIS 1.7.4. I've been reading a CSV file and view it as a Shape Layer. With the help of attributes from the File ...
3
votes
1answer
186 views

Create a band mask based on pixel locations, not in pixel values

I have this image loaded in QGIS, with two possible values for the pixels: 1 = orange, 2 = blue For simplification, assume it represents a province of a country. I want to extract just the part of ...
3
votes
1answer
51 views

multi-line attributes in composer

I have a multi-line text attribute in one of my layers, but when I try to display the data using the 'add table' function in Composer, it just gives the text a single line, not enough room to fit. ...
3
votes
1answer
455 views

Masking/removing polygons from shapefile

I have a shapefile containing the road traffic noise of a city. The shapefile has 5 columns, where 'noise_in' (noise interval) ranging from 1-5 is included. I want to remove/mask the road noise from ...
3
votes
4answers
647 views

Is there a union function for multiple layers comparable to ArcGIS in open source GIS like QGIS?

I need a union function for a lot of polygon layers (protected areas of all kind, nature, water etc.) comparable to the union function in ArcGIS. I have only the desktop version from ArcGIS and so it ...
3
votes
3answers
5k views

Problem with spatial reference system / shapefile projection

I am new to using QGIS and having some problems getting some shapefiles to project correctly. I am using publicly available shapefiles for New York City municipal boundaries found here: http://www.nyc....
3
votes
1answer
822 views

Tracing Boundary Around a Polygon Shapefile in QGIS

I'm looking to create a boundary around this shapefile of street blocks to have show the city limits in QGIS. I tried this solution, (Settings > Snapping Options and enabling the "Avoid Int." ...
3
votes
1answer
247 views

Generating polygons with streets as borders using QGIS?

I have searched online for almost a week and can not find an answer to my issue. I need to generate polygons from street borders in a given city. I have downloaded data from openstreetmaps and ...
3
votes
2answers
156 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
43 views

Distance matrix tool, how to include distances at 0 metres?

I have used the Vector -> Analysis Tools -> Distance matrix to merge two datasets by the closest points. But in my output csv file, the points that match exactly, or that has 0 metres between them ...
3
votes
4answers
3k views

How to remove vertices or lines within a polygon?

I have transformed a *.dxf-file into a polygon shape-file. In many of the polygons i have lines whicht do not belong there but i can not delete them as i normally delete vertices on polygons by ...
3
votes
0answers
143 views

How to fetch openlayers layers from pyqgis? [duplicate]

My objective is to fetch maps provided by openLayers, as in openLayers_plugin, from a stand alone python script. I would like to get it superposed to my shp file. As can be read on http://www.qgis....
3
votes
1answer
7k views

How do you import simple xyz in QGIS

I have found out how to get tab-delimited X,Y data into a layer but the Z field value is not given as an option on import? I tried to edit the attributes to add and define a new field but it keeps ...
3
votes
2answers
2k views

Normalize raster values to 0-255

I need to normalize the values attained from a band ratio to 0-255. I'm using QGIS. How do I do this? Any ideas?
3
votes
1answer
423 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 ...
3
votes
1answer
63 views

Dynamic Linear Referencing of events in QGIS from Excel or CSV using virtual layer

I have a PostGIS table with a geometry type LINESTRING M to represent routes. Here is the table specification: CREATE TABLE routes ( fid serial PRIMARY KEY, r_name text NOT NULL, geom geometry(...