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

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2answers
53 views

Creating an artificial coordinate system to plot a garden experiment

I am trying to map plant death in a garden experiment. The location of the garden doesn't matter, I just care about each plant in relation to the others. They were all planted on a grid system. My ...
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1answer
30 views

QGIS- extract raster information into a point return nulls

I have a 1) raster layer and a 2) point layer. I want to extract the pixel value to each point, but it is not working when using this tools (QGIS): plug-in "Point sampling tool" (the new shapefile ...
2
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1answer
20 views

How to extend an OSM or raster area in Qgis (into 'No Data' area)?

I need to do the opposite of clipping down a raster (or SHP file) in Qgis (or Gdal, Python etc - even R if someone can provide the script). I have a dataset from Open StreetMap (*.OSM) which includes ...
3
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2answers
114 views

How to extract part of string after '*', '~', '-' or '#'

I have strings like this: 234/1-1 3345#5 11/2~10 6754*15 It needed only rightmost part of string after '-', '#', '~'or '*' . I figured how to extract when there is only one sign for example '~' ...
2
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1answer
67 views

How to get attribute values from vector features visible in the qgis canvas

I have a vector layer (grid). Currently I select some tiles with the select tool and paste some python code to get information about these features. layer = qgis.utils.iface.activeLayer() ...
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1answer
32 views

How to add a node/vertex in a QGIS edit session?

I'm doing some polygon (boundary) cleanup, and am wondering if it is possible to add a node/vertex to a set of selected polygons or even a single polygon. By the way, the QGIS topology editing tools ...
2
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1answer
62 views

Update raster color ramp with new min/max values using python?

For a script, I want to update the exsiting min and max of a colour ramp with a new one. In the image you can see what I want to update. To do so I tried to follow this thread. I tested the ...
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0answers
26 views

USGS ArcGrid converted with GDAL to GeoTiff

I downloaded an USGS NED File in ArcGrid Format. I converted it with GDAL-plugin to GeoTiff. But the dimensions are wrong. Is there a possibility to "stretch" the GeoTiff in the right dimensions? I ...
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0answers
54 views

QGIS Attribute Question

I am trying to create a script that will take selected features from one layer and search for the specified attributes related to a column name. in my case 'id'. What I am having trouble doing right ...
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0answers
14 views

Getting Color Infrared from NAIP WMS Server on QGIS

I'm having a terrible time getting color infrared imagery from an NAIP WMS Server with QGIS 2.14.3. I use the "Add WMS/WMTS Layer" button, add a new server with the URL from the WMS link on ArcGIS ...
2
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0answers
41 views

problem using qgis spatial join in a python script or modeler : no results [closed]

I'm trying to create polygons from points layers. Each layer contains one point to avoid troubles due to superposition of polygons. I detailed the context here : How can I add output vector to a list ...
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1answer
43 views

Road Graph plugin routing on a virtual numeric field does not work

I'm trying to calculate the shortest/fastest path based on a 'dynamic' virtual field with the road graph plugin. The speedvalues are based on a combination of other ppvalues: eg field GFBscore. But ...
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1answer
22 views

QGIS Clip of layer with several points

I have two shapefiles: 1) one with several points with a buffer around each separated point 2) another which is a single polygon with several characteristics (therefore it has several polygons inside, ...
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1answer
24 views

I keep getting the same error when trying to clip a raster

Error: Cutline feature without a geometry. Consistently get the above error when trying to clip a raster. I have looked at all the other questions relating to this and tried all the 'fixes' however I ...
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0answers
56 views

Cannot run QGIS algorithm with python script without interface

I'm trying to run the QGIS 'intersection' algorithm from a Python script: (Working with Ubuntu) #!/usr/bin/env python # -*- coding: UTF-8 -*- import sys from qgis.core import * from PyQt4.QtGui ...
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0answers
34 views

How to remove circles from new polygons in QGIS? [closed]

I've just started using QGIS (2.6.0-Brighton). Every time I create a new polygon, a circle appears in the center (see below). I thought this might just be a feature of QGIS editing that helps you to ...
2
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1answer
69 views

How to convert raster (big size) to points?

I have a raster : population density of Ivory Coast. I need to convert it to points, but I met several problems because of the size I think. Here is what I tried : 1) GRASS GIS 7 command : r.to....
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1answer
27 views

QGIS: how to label a continent map with distinct values from shape file?

I have a continent shapefile containing the names of its different countries. Unfortunately, many of these countries have more than one entry (i.e. more than one row in the attribute table). ...
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0answers
19 views

64Bit Applications installed with QGIS/osgeo4w

Is python 64bit and gdal 64bit automatically installed when QGIS 64bit is installed via osgeo4w 64bit? I currently have a custom 64bit python and gdal setup on my pc. However, this setup causes some ...
1
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1answer
26 views

Atlas Generation output from QGIS is returning empty files

I have set up a project and print composer to generate an atlas so I can print off some 300 pages of feature coverages. I have selected "Preview Atlas" and entered in settings for Atlas Generation ...
2
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0answers
29 views

QGIS segmentation fault related to numpy on Ubuntu

I'm running QGIS 2.14 on Ubuntu 14.04 and everything's been working just fine until I upgraded a few Python packages via pip this afternoon. Since doing that, QGIS crashes with a segmentation fault ...
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0answers
21 views

Merging Shapefiles in a Folder using pyQGIS [duplicate]

I was reading the QGIS Python Programming Cookbook (page 74) trying to learn how to merge shape files because I need to do it for what I'm doing. I was using their example just to try it out though. ...
2
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1answer
47 views

Change percentages to Real numbers in QGIS?

I'm trying to convert percentages to real decimal numbers so they'll display properly. I tried to_real() but maybe I did something wrong. Any suggestions?
1
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1answer
18 views

CRS different after r.reclass through QGIS different than source raster

According to the properties, my output raster is in a different projection than the input after running GRASS r.reclass through QGIS. Does anyone know if this is just a fluke and I can simply select a ...
1
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1answer
18 views

saving a SVG marker to a layer for sharing

I have a layer which consists of point data. I have switched the symbology of the layer to a svg image that I loaded in. To maintain the symbology I went to LayerProperties>style and then i saved the ...
2
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1answer
37 views

Is there a way to automatically displace colliding labels?

I have a PostgreSQL table, which i'm loading on QGIS Essen, that relates many rows to the same object and all this rows have distinct values in the field i'm labelling the objects with. Hence, when I ...
2
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1answer
26 views

How to include QgsRasterBandStats in plugin

I'm making a plugin were i want to get the min and max value of a raster. When i tried the following code in the qgis python console it worked fine but in my plugin code i get the following error ...
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0answers
26 views

How can I style a feature that has multiple values for the same field?

I'm opening a PostgreSQL Table on QGIS which has multiple rows related to the same object (think of how you'd register distinct apartments on the same building). I do get to style it based on any of ...
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2answers
35 views

qgis cluster gdal Unknown option 'INTERPOL'

I am running cluster analysis from image analysis menu of saga provider in qgis. I use the qgis GUI from processing tool box, I call saga modules. I got same error in many other algorithms. I can ...
0
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1answer
18 views

CRS USA_Contiguous_Albers_Equal not working

I have selected the USA_Contiguous_Albers_Equal_Area_Conic, yet the map is showing a different projection. It worked when I started the project and something went wrong after I did a "print composer"....
1
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1answer
41 views

Create Vector Grid from a features Extent with PyQGIS [duplicate]

NOTE: THIS IS FOR QGIS 2.14.1 and uses VectorGrid instead of CreateGrid also though the question How to generate a grid programmatically in Python without GUI? is answered fantastically the PyQGIS ...
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0answers
34 views

How to export a training shapefile as an XML spectral signature file via QGIS?

I recently used the answer from Orfeo Toolbox object based classification in QGIS tutorial/workflow to perform an object base segmentation on a spot image i acquired a while ago. I tried both of the ...
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0answers
38 views

Is it possible to view Mapillary photos on QGIS?

Mapillary (link) provide streetview-like photos of many areas. There is a plugin available for the Openstreetmap editor 'JOSM' which provides an interface to view the photos (which is sometimes more ...
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0answers
33 views

Setting up a simple catchment area for shops using QGIS?

I would love to set up a catchment area around simple dots on a network map. The catchment should be separated by different range-areas (50, 100, 200m), just like isochrones. I tried the GRASS plugin ...
3
votes
1answer
104 views

Labelling only part of the row

I have a column (see below) where I want to label only part of the row. Example: 16-23-1-01-7 -a -00 I want to label only: 7 -a Is it possible in QGIS?
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0answers
16 views

Can a QGIS model be executed as part of a script?

Can a QGIS model be executed as part of a script? e.g. PowerShell script copies over source data using FTP, then runs the QGIS model, and finally emails success/fail of the process
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1answer
19 views

Maximum likelihood not working in QGIS SCP?

I was trying to use maximum likelihood in SCP QGIS, but a warning come out "Information [18]: Select at least one signature", and when I selected all signature, it still won't run.
4
votes
1answer
50 views

Where are the QGIS Style Manager settings stored?

I would like to export all the icons defined in QGIS Style Manager to another QGIS installation in another PC. I've been looking in Windows Registry inside "HKEY_CURRENT_USER\Software\QGIS" but I ...
4
votes
1answer
90 views

Join / merge lines that touch and intersect in QGIS

I have a large dataset consisting of lines/polylines where I would like to join/merge the lines that touch / intersect. Each line has an individual ID and there are no common attributes I can use for ...
1
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1answer
27 views

Determine what is activated by QAction.activate(QAction.Trigger)

I'm trying to build a plugin for Qgis where I want to use some functions of a default plugin. I would like to control the options that the user are supose to fill in while using the Interpolation ...
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0answers
56 views

Can QGIS do automated spatial ETL? [closed]

Can QGIS do automated spatial ETL? ... especially the automated point I'm aware of tools like FME, Talend, etc. but price is a concern, so I'm looking for FOSS alternatives that provide spatial ETL ...
2
votes
1answer
51 views

How to remove all layers from a group

I want to remove all layers from a distinct group. root = QgsProject.instance().layerTreeRoot() the_group = root.findGroup("my_group") parentGroup = the_group.parent() I think I have to loop the ...
3
votes
1answer
64 views

Label QGIS diagram sector with percentage etc

I'm working with QGIS 2.14.3, using the diagrams function for vector layers. Is it possible to label each single diagram sector with an attribute / calculated percentage? In the layer properties tab / ...
4
votes
1answer
55 views

How to remove ghost lines around polygons in QGIS 2.12?

I'm trying to remove the very thin, yet visible white "ghost" lines in between polygons. You can see This in the image below. Hopefully you don't have to strain your eyes to see that there are very ...
1
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1answer
30 views

Rasterize points in a map : result is not leasible. How to make the raster (points) bigger?

I have a vector layer (points) that I rasterized based on one attribute of the vector layer. I chose the GRASS GIS 7 command : v.to.rast.attribute. The raster layer appears in the map, but is not very ...
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1answer
36 views

Print Composer in QGIS exporting different image

I prepared a map in the Print Composer of QGIS. The scale of the map is 1:150,000,000. I imported the Thunderforest Pioneer base layer. At the scale I used, country labels do not show when working on ...
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0answers
18 views

Cropping vector map into tiles with QGIS - how to get around shapefiles which have stray points on boundary of tiles?

I am trying to use QGIS to generate a set of tiles in Shapefile format from a vector coastline map. My script is correctly generating the 5x5 degree tiles I want, however a few tiles clearly have ...
3
votes
1answer
33 views

Configuring Project CRS to reflect degree coordinates

seems like this is a common problem, but posts with similiar questions did not solve my problem. I have close to zero GIS background so apologies for my ignorance. My goal is to extract only a ...
1
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1answer
47 views

Geographical weighted regression

When i run a geographical weighted regression in QGIS, this command pops up 'NoneType' object has no attribute 'crs' See log for more details and no regression analysis will happen. Does anyone know ...
2
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0answers
19 views

difference in behavior between merge from SAGA and merge from QGIS geoalgorithms

I'd like to know what I'm doing wrong with the merge algorithms in Python. I have several shapefiles (polygons) ending in 'LNA', 'LNC', 'LDA', and 'LDC', and I'd like to merge them depending on ...