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

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How to interpolate data using quantum gis?

I am trying to interpolate distribution value of rain using IDW (inverse distance weighting) method using quantum gis. What steps do I need to undertake? The input layer data which I used there are 2 ...
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120 views

How to export the contents of a QGIS relation?

I have created a 1:many relation in QGIS 2.10.1 with Project Properties>Relations. When I select a map feature with the Identify Features tool, a Feature Attributes window (widget?) appears. How do ...
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19 views

In QGIS, add to existing dem tiles and expand corresponding contour coverage within a project

In my first QGIS project I have dozens of digitized layers that have spread beyond the contour and dem tile area that I started with. Please recommend how to safely expand or replace the dem and ...
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61 views

osgeo4w not installing processing tools in QGIS toobox. [duplicate]

I have uninstalled and reinstalled QGIS several times from the OSGeo4W application. I have done this with no problem on several other times, but now I cannot get the tools to load. Most of the help ...
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36 views

Explanations for attributes QGIS

I have one column in my attribute table with attributes "1", "2" or "3". 1 = normal route 2 = special route because of the event (every year) 3 = special route because of the event and construction ...
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43 views

Query ShapeFile to get informations from coordinates

I have a shapefile that represents all the Hydrological Basins in the world. You can download the file from here: http://www.fao.org/geonetwork/srv/en/resources.get?id=38047&fname=...
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82 views

Map with just City/Country/River/etc names.

I am looking for a plug in or a map, that only has the names of the countries and cities and other urban and/or geographical features. Does anyone have or know of such a map/plugin. I'v e been ...
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137 views

Polygons in one layer have different attributes

Is it possible in PyQGIS to have in one layer more polygons and some would have one set of attributes and another different? E.g. Polygon_1(name, size, average_age), Polygon_2(name, size, ...
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93 views

How to get PostGIS DB name from QGIS layer?

I'm writing a custom Processing script that needs to know which database connection a vector layer resides in. I can't find anywhere in the API a function to return this information from a layer. So I ...
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1answer
348 views

Loading Natural Earth *.prj file into QGIS 2.10.1?

I have found solutions for this problem in other versions of QGIS, but none that apply to the newest version 2.10.1. Whenever I try to import a Natural Earth Raster projection that is a prj file I get ...
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2answers
92 views

How to put a frame around a legend using QgsComposerLegend?

I can already see this being a simple answer but I'm stumped with this. I want to create a frame around a legend created by a PyQGIS script Code snippet is: legend = QgsComposerLegend(c) c....
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1answer
103 views

How to read non-spatial data using PyQgis?

I'm generating maps with QGis. What I do is generate a bunch of non-spatial data on a set of cities (using VBA), and still using VBA, generate a python code that will automaticaly output general map ...
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133 views

QGIS imported geotiff rendered as perspective view, how to change to top

I've created a GeoTiff that should have GPS coordinates in it using AgiSoft. When I load it into QGIS, it renders the image in a perspective and I want to always see the image from the "top" down. ...
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2answers
670 views

Opening HDF data in QGIS on Ubuntu?

I try to open modis aqua data (HDF5 format: A2015208112000.L2_LAC_OC.nc) on QGIS 2.8 ver. And an error appears: No extra dimensions found. Could someone help me to solve this problem?
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2answers
151 views

How to join the attributes table from one input layer to another layer with unique id using python

I have one input layer with the attibute values and i wanted to join the attribute table of the input layer to the another layer with unique values using python. gis.stackexchange.com/questions/89706/...
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1answer
342 views

Remove lines from inside a polygon in QGIS

Through a "dissolve" process in QGIS, I achieved some polygons that have some fails, like this one in the screeshot: Is there any automatic process I can make in QGIS to remove those lines inside ...
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1answer
196 views

QStringList() error in plugin of QGIS 2.10

I have made a Dialog in PyQt for use it like a plugin under QGIS 2.10 The Dialog works fine like a standalone application, but if I try to call it like a QGIS plugin, I get this error: ...
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1answer
191 views

Failed to create memory layers in QGIS application on Linux

I have written a python class which reads properties of map layers from an XML file and creates appropriate memory layers. I have developed and tested this code with QGIS 2.8.2 on a Windows 7 machine (...
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116 views

Creating polygon grid with un-even spacing between research plots?

I have an orthomosaic of a crop field with small research plots (3.8 X 1.44 m and 0.22m b/w plots and 0.50m b/w range spacing). I would like to create a polygon layer using this information. After ...
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1answer
291 views

Spatial join of a single point to multiple polygons

I have a point layer which I want to spatially join to a polygon layer (bring in the attributes). This works fine unless there are overlapping polygons, if so the QGIS spatial join tool will only ...
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1answer
111 views

Finding the date of acquisition of Google maps in QGIS

How do i find the date of acquisition of the Google map on QGIS? Please help.
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1answer
210 views

How to get the coordinates inside the polygon using python

I have a polygon and using this code snippet we can get the coordinates boundary of the polygon. canvas = qgis.utils.iface.mapCanvas() aLayer = canvas.currentLayer() coord = feat.geometry().asPoygon()...
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3answers
205 views

Processing modeler: how to dissolve a vector layer and sum the attributes

I have a complex workflow prepared in the processing modeler, but I'm missing one step to link all the model. I need to dissolve a polyline vector in a single line vector that has as attribute the ...
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1answer
270 views

What's difference between Topology and Check Validity in QGIS?

I would like to know what the difference is between the Topology Checker and Check Validity tools? Is there anyone who knows of a good document or tutorial that explains functions of these tools? ...
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502 views

Importing raster adf files with the additional files

I am trying to import a vegetation data raster in Esri GRID format from the USDA into QGIS. One file ("w0001.adf") can be added using "add raster", but the attribute table and other info register as ...
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3answers
154 views

What's the parameters of heatmap formula on QGIS?

I want to calculate the values by hand to know which parameters effect the result in the image, but i couldn't able to do that because i didn't understand it. I tried with 500 mt and 1000 mt radius ...
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297 views

Layers with the same CRS in QGIS do not line up

I am busy with a project where I have to layer a .dxf and a .kml file but the layers are not lining up. The .dxf file's coordinates are completely wrong and the scale also does not appear to math up ...
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1answer
161 views

How can I create polygons for a 3D map from a DEM in grass/qgis

I have a SRTM 30m DEM of my area. I want to create a physical 3D terrain map from it (from felt, 3D printer, you name it). I have two questions about this process: With grass r.contour I created ...
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1answer
103 views

QGIS import OpenAIP

I have files from OpenAIP (http://www.openaip.net). How can I import them ? Format available are : .aip .cup .dat .aip is xml file. For point : <OPENAIP VERSION="960678" DATAFORMAT="1.1"> &...
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1answer
435 views

Is there a way to set the character encoding for all layers at once?

I have to set the character encoding forall layers from system to UTF-8. Is there a way to change this in all loaded layers at once? I'm using QGIS 2.8.1 on Windows 7.
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2answers
121 views

How to use r.mapcalculator to change values within a raster cost map to negative

I have created a cost map in r.cost module in GRASS (through QGIS). This is actually a distance map from a protected area and distance from protected area has been calculated in both directions. How I ...
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1answer
34 views

QGIS Coverage help

I am using QGIS 2.8.2 and everytime I try to load in a coverage type Shapefile, like forest density or population density it all comes up as the same color, but has the sections marked for the density/...
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62 views

Why does the Contour Plugin failt to load in QGIS Valmiera?

Whenever i try to load the contour plugin. I get the error as follows: The same happens to when i try to load Qgis2leaf plugin... An error has occured while executing Python code: Traceback (most ...
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1answer
108 views

Dissolve Polygons by attribute leaves empty spaces

I am trying to dissolve polygons based on the same attribute using QGIS 2.8.2 (Wien). I use Vector, Geo Processing Tools, Dissolve and then I select the attribute. The data is Postal Sector in Uk and ...
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2answers
171 views

Getting attribute table from WFS data source

I am attempting to get some WFS 2.0 INSPIRE data from the Finnish meteorological institute into a table format of some kind. Is there any software which can easily grab the attribute data for the WFS ...
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1answer
167 views

Labeling only line vertices in QGIS?

I want to only put labels on the vertices of the polylines. I can use the data defined features to place a label at specific points, but not at multiple specific points. Is it possible to label only ...
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1answer
90 views

QGIS WGS84 issues

I potentially have a problem with my QGIS project, where I am attempting to digitise a relatively small map, and part of the project requires a calculation of the area of each of the parcels of land ...
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1answer
81 views

How to delete char in table attribute in QGIS 2.6.1

I need to label many items but in the table attribute field there are some char (#F) for every item that I have to delete. The length of the description are not always the same. I create a new field ...
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1answer
56 views

Different values after clipping

I have a satellite image from Landsat TM. I want to clip my area so i created a polygon and thru Qgis --> raster clipper I am trying to clip my area of interest. I noticed that the results have ...
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1answer
152 views

How to remove group filter applied via Python-console (setSubsetString) of QGIS?

I need to quickly applie (and then change/remove) the same filter for about 100 layers in my QGis project (all put together in one group). Since there is no implemented solution right now (a feature ...
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1answer
131 views

How can I implement animation with lines using QGIS TimeManager?

Among all the examples I saw, I can only find those with animated dots. I need to implement a time slider based on each link's capacity, and display different colours according to the magnitude. ...
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1answer
15 views

QGIS Graphical Modeler Help editor does not save

Is there a special way to save whatever text you're writing in the Help Editor for a QGIS Model? I've been trying a few times, apparently just after I click ok, even though I immediately click "save" ...
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1answer
222 views

Heatmap failing in QGIS (2.8.2-Wien)

I am super new to QGIS so I may be doing something really dumb, but it doesn't seem to work to create a heatmap in QGIS Desktop 2.8.2 (just downloaded this yesterday so I think it is the most current ...
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1answer
130 views

How to downgrade from Processing 2.6 to 2.2?

I have QGIS 2.8.2 installed and Processing Toolbox 2.6. I want to test a thing and I need to install processing Toolbox 2.2 in QGIS 2.8.2. Is it possible? How can I do that?
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1answer
106 views

Is it possible to change data (attributes) in the .csv of a data vector layer and QGIS automatically adopt this?

I have a .csv with data for 300 points: Each column on the .csv is a particular object and the cells define the amount that is available in each point. If I need to change this amount, is it possible ...
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1answer
179 views

ST_Intersection for polygons

I'm looking for a query that returns overlapping areas of two tables with polygon geometries. Using row_number() over() the entries of the gid column are not unique in the case of dumped multipolygons....
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1answer
379 views

How do I import a NMEA file into QGIS 2.8?

I have some NMEA data recorded in a file - this is not a realtime application. How do I import that into QGIS 2.8?
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94 views

delete a space with the field caculator

I would like to delete the space in this number like this 'F00 089' with the field-calculator. Is theres a function in the field-calculator? ! see my screenshot
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1answer
61 views

“Get” results of PostGIS [closed]

I am getting warm with post PostGIS. I am working in the Command Line. What I am wondering is how do I "get" the results of PostGIS. So imagine I have this select name, neighname from neighborhoods ...
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1answer
429 views

How to update raster color ramp with new min/max values using PyQGIS?

I'm trying to update a single band psuedo color renderer with new min/max values from the python console. All the code samples i have been able to find deal with constructing a renderer from scratch, ...