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

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How to equally space points in a line using QGIS? [duplicate]

How do you place points in a straight line the same distance from each other in QGIS? Thanks
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2answers
10 views

QGIS: Get data in raster DTM from vectorpoints

I have a vector layer of points. Can I get an output from a rasterlayer which contains DTM-values (height) determined by my points placement?
3
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12 views

Send signal when attributes modified - QGIS 2.6

For a QGIS 2.6 python plugin, I am trying to send a signal when an attribute value is changed (values for an existing feature are updated or added and the attribute form dialog is accepted). This ...
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1answer
16 views

NDVI composite image

I have downloaded MODIS NDVI images of 12 months. I would like to create just 1 image with the mean values. I tried using IDRISI's 'NDVI compositing utility', but I get an error. Is there a way to do ...
2
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0answers
19 views

Shapefile layers in QGIS don't display unless I zoom out

I have two shapefile layers in a Qgis project that have problems with zooming. One is a line I copied/pasted in a new layer from a set of height contours and the other one is a polygon layer I created ...
1
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1answer
11 views

Why use QgsFeatureRequest() when iterating?

I am unclear on why one should use QgsFeatureRequest() when iterating over a file’s features. Let’s say I would like to print out all IDs in my currently active dataset. Now, most examples will ...
3
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2answers
22 views

Qgis - Projection Problem with EPSG:2272

I work in both Qgis and ArcGIS. Most of my data has been created using ArcGIS and all of my data should be in the EPSG:2272. When I add my data to Qgis, it does not recognize my projection and gives ...
3
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1answer
15 views

How to always disable the “add saved file to map” checkbox in Save as …?

I often use the "Save as.." dialog and just want the exported geojson file there. But he always enables the checkbox "add saved file to map". I really dislike it that way and it does not make any ...
4
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2answers
33 views

Adding Eastings and Northings as attributes automatically to a point layer in QGIS

I have a point layer that I am adding to and am working in British National Grid. Two of the columns are Easting and Northing. When I add a new point I want these two columns to be filled out ...
4
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1answer
19 views

Start QGIS with virtualenv Python

is there any means of telling QGIS to use a different Python installation than the default, system-wide one? E.g. use some virtualenv Python /myvirtualenv/bin/python instead of /usr/bin/python? ...
2
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1answer
16 views

Visualising a raster PostgreSQL table in QGIS

I have imported a raster tif image into PostgreSQL with this command: raster2pgsql -s 32643 -I -M filepath.tif -F -t 100x100 public.databassename > filepath.sql And imported the output SQL file ...
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24 views

3D interpolating

Our final year project domain is soil contamination modeling. We collected soil samples at the depths of 0.3 cm ,0.5cm , 1cm , 1.5 cm in about 25 locations. We considered 8 contaminants- p h, sodium, ...
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18 views

seeking help to build QGIS from source code with microsoft visual C++ on windows 7 [on hold]

how to build QGIS with Microsoft Visual C++ 2010 Express Edition on windows 7
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0answers
17 views

How to select the features by freehand in qgis using python programming

I have one polygon layer with 10 features. when i draw a line by free hand on the polygon layer it has to select the features. But when i am using qgis.utils.iface.actionSelectFreehand().trigger() ...
4
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1answer
31 views

Qgis2Threejs returns empty page

When i try to make 3D scene from DEM with Qgis2threejs it creates a empty html page. I also try to make 3D thematic map from shapefile with the same result. I have also check my browser and it ...
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0answers
21 views

QGis measure tool does not continue to measure within point symbol

We are using QGIS more and more, however, today a colleague noticed something strange when using the measure line tool. We have point features and different symbols of different sizes and colors are ...
2
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0answers
24 views

Efficiently generate Voronoi layers in qgis via Python

The following python commands both appear to function when called in qgis 2.6 to generate Voronoi diagrams: processing.runalg("qgis:voronoipolygons", pointLayer, 1, None) ...
2
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1answer
54 views

Spacing a set of points

I have a shapefile of a set of points that I want to space out. I DO NOT want to do this using line interpolation as I run the risk of placing a point where there wasn't one before. I can load this ...
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2answers
38 views

How to set the QGIS display to show decimal degrees?

Using QGIS 2.6.1 Brighton. I am trying to set the CRS for the project to display Decimal Degrees, where it is defaulting to Feet. I can change it in the Properties Dialog, but it does not change it, ...
2
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1answer
21 views

qgis : how to merge attributes of points and lines

I have a point vector-layer and a line vector layer. All points of the point layer are positioned on the lines (railway lines) of the line layer. I would like to add the attributes of the line layer ...
2
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1answer
36 views

Merge multiple bus stops with same name

my question is similar to this one, but it's not answered sufficiently: How to merge points (bus stops) in QGIS manually or programmatically? I have OSM-transit data with bus stops. Some stops have ...
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0answers
5 views

Unable to execute the algorithm using SAGA LS factor

I tryed to calculate the LS Factor at SAGA, using a slope raster and the area raster, both at the same EPSG, and the error:Unable to execute the algorithm the error means something with the coordinate ...
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0answers
12 views

Error when using r.watershed

When i am calculating LS Factor using Grass r.watershed the error "Raster map or group not found" (image below) keeps turning on. I don´t understand why this error happens if i am using a elevation ...
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0answers
12 views

Manifold GIS Scripting/Queries — query a web page and scrape page source?

I'm using Manifold v8.0 to process some data. The process involves some scripting and querying, but one step currently requires me to go to a website, enter some data into a form, read the results of ...
2
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0answers
7 views

QGis - WFS and joins

I'm trying to figure out whether it's just me, or if I'm forgetting a setting. I have a shapefile which I make available for WFS-requests. Now I added a join (to a MySQL table). I tried playing ...
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1answer
18 views

Adjust Fill style behavior QGIS

Does anyone know how one can change the Fill style option in QGIS? I need to use a diagonal pattern that does exist, but I need to adjust it. I have a cartography specification that defines the ...
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0answers
12 views

How to show features in Layers panel in QGis?

I'm new to Q-Gis, so forgive me if that's an obvious question. How can I see the features in Layers panel in QGis in a nestef form? Thanks! Dani
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2answers
34 views

QGIS keyboard shortcut to launch a 'Select by expression' query

I can't find if it is possible to launch a 'Select by expression' query (not to open the dialog) with a keyboard shortcut. I can't find this option in the Settings > Configure shortcuts list... If ...
3
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1answer
43 views

How can I find the version of a toolbox used in QGIS

I am using QGIS 2.6.1 Brighton on Xubuntu. The QGIS-install comes with several default toolboxes. Orfeo Toolbox for image analysis is one of them. How can I find out which version of the Orfeo ...
2
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1answer
63 views

Run processing toolbox outside QGIS in standalone app

I am developing a standalone app in Python, using QGIS libraries including processing algorithms. I am developing in Linux environment and I put the libraries in a folder. Also I put the processing ...
3
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1answer
17 views

How to shift a raster in QGIS?

I'm looking for a tool or a plug-in for QGIS that would allow me to shift rasters to new coordinates. An equivalent of ArcGIS' Shift tool would be the best option. I know I can edit the world file ...
2
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1answer
21 views

QGIS : Disable a line in 'Select by expression' dialog

I would like to disable some lines in the 'Select by expression' dialog (QGIS 2.6) but I can't find whether it is possible or not, and if yes, how to achieve that. I have tried several characters ...
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1answer
18 views

Creating Stream Order

I'm new user of this software, please can somebody guide me, how to calculate stream order in QGIS or GRASS GIS, step by step.... mean commands and how to calculate watershed in this.
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15 views

Connect two contour line with calculated line lenght

Is it possible to make plugin for qgis like PEGGER for arcview 3.2? Problem is, how to make path over contour lines with a grade in percent Formula is: K= e*100/G*M ; K=10*100/0.08*10000=1.25m K- ...
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0answers
41 views

Calculating vector area in QGIS

I have calculated a viewshed (ZVI) in OpenWind and opened the raster in QGIS I have then converted the raster to a vector When I open the attribute table there are 4682 rows (features) and there is ...
1
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1answer
37 views

How to create a text file containing layer names in QGIS?

My QGIS ToC contains layer groups and some layers that do not belong to any group. I would like to create a text file containing the name of those layers that do not belong to any group. Is there an ...
3
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0answers
24 views

QGIS algorithms do not work on copies of shapefiles?

I'm using QGIS 2.6.0. I'm trying to run various algorithms such as "SAGA/Shapes-points/remove duplicates" & "SAGA/Shapes-Grid/Add grid values to points" through the sextant toolbox. When I run ...
2
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1answer
22 views

Error converting a raster to polygons

When I am converting a raster using the polygonize tool, I get this error: ERROR 4: 'C:/Users/Vitor/Desktop/Cartografia EE_Portimo/COS RASTER/cos_raster_reeditada.tif' does not exist in the file ...
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1answer
43 views

How to automatically create 10,000 sets of random points for further analysis in QGIS?

I'm using QGIS and would like to know if I can automate generating multiple sets of random points and mean distances? I have a data set consisting over 600 coordinate points for Mistletoe across ...
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0answers
11 views

How to relate data values from two raster layers?

This is my second posting ! 1 Background I have a number of ASCII files containing a set of single values X, each set in a 1km x 1km grid – the start of each file looks like this: NCOLS 700 ...
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13 views

How can i perform area calculations in a raster file?

I would like to know if is possible and how can i calculate all areas or parts of it in one raster? Can i do it using the raster calculator? All help is appreciated, Best regards
3
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1answer
44 views

How to display OSM relations (in QGIS) from osm2pgsql populated PostGIS DB

I have a PostGIS DB populated with OSM data (osm2pgsql, standart.style). Now I would like to display a hiking trail (http://www.openstreetmap.org/relation/51855). It would also be fine, if I just ...
5
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1answer
253 views

Is it possible to have dynamic layer names in QGIS project?

I have a QGIS project with layers, based on PostGIS SQL queries that use current date. Since the data in the database changes, these queries return different data every new day. Is it possible to ...
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1answer
23 views

Tools to export shps from Oracle database

What open source tools could be used to export shapefiles from an Oracle database. I have tried using QGIS but it does crash way too much.
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0answers
15 views

How to get the same cell size after and before been rasterized [duplicate]

The following information were used for rasterization of the land cover of Nigeria but got different cell sizes. The input cell size and the measured cell size of the rasterized are not the same. ...
0
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1answer
30 views

Got different cell sizes from a rasterised data

I'm trying to rasterize the Land cover data of Nigeria which was obtained from FAO database. During the process of rasterizing the land cover data, I used the following information which gave ...
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0answers
21 views

Why does my “Zoom to selected rows” Shortcut not work in QGIS 2.6.0?

I´ve changed a shortcut, in this case "Zoom to selected rows". But now it stopped working. The new shortcut never worked and the originally as well is not working now. The icon gets activ when doing ...
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2answers
49 views

QGIS batch shp transform

I have a large number of shape files in OSGB (EPSG:7405), with no .prj file that I would like to convert to WGS84 (EPSG:4326). Can you let me know if this is possible in Qgis and, if so, how, and, if ...
1
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1answer
31 views

Is it possible to create tiles with transparent background using Qtiles?

I had created the tiles from shapefile using qtiles plugin in QGIS and that shapefile layer is a label layer created using MMQGIS plugin. But the thing is I want that tiles with transparent ...
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1answer
11 views

Open and split a 4 channel RGB picture

How can I split an 4 channel rgb pic in qgis? With the value tool I can see 4 channel. I tried to use the RGB to PCT tool but I always get an error (File "C:\PROGRA~1\QGISBR~1\bin\pct2rgb.py", line ...