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

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33 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 ...
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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"....
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1answer
33 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
32 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
34 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
31 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
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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
18 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
48 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
86 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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0answers
25 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
55 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
62 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 / ...
3
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1answer
51 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
29 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 ...
1
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1answer
34 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
17 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
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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
45 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
18 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 ...
2
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1answer
30 views

plugin builder problem with compiling(probaly)

I m trying to make a new plugin with the use of plugin builder. But i stumbeled across a problem when following this tutorial. I get stuck on the point that i have to compile the plugin. With the ...
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1answer
39 views

What is the correct (QGIS) syntax for a masked PostQIS spatial query?

What is the correct syntax if I want to query a masked region from PostGIS from inside QGIS ? The data is from "planet_osm_poly" (imported via osm2pgsql) and I'd like to use a polygone from a ...
1
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1answer
47 views

QGIS problem with positions of imported waypoints

I'm a newbie to QGIS. The waypoint data was collected on a Garmin etrex legend H, with the grid set to OSGB36. Using Garmin's Basecamp software, I saved the waypoints as a gpx file (also xml etc ...
1
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1answer
36 views

Display selected features with same point geometry

I have a point layer and some features have exactly the same geometry. When I make a selection it seems that some features are not selected because they do not display with the "Selection color" as ...
2
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1answer
31 views

vegetation classification from only the panchromatic band

I am mapping mangroves over a period of several years using satellite imagery. I use QGIS semi automatic classification plug in. Supervised classification (maximum likelihood) as I can visually ...
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0answers
45 views

False calculated slope?

After the DEM creation, I wanted to create slope layer. However the result has not satisfied me. I don't think the slope map is correct. Have you ever encountered false calculated terrain map?
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2answers
26 views

Add raised features to digital terrain model in QGIS

I have a DTM onto which I need to 'stamp' a series of raised embankments. The DTM is a raster grid (in m above sea level) and the embankments are polylines containing the crest height (also in m.a....
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2answers
134 views

How to find out whether a satellite image is atmospherically corrected

I have a satellite image and I am not sure whether an atmospheric correction has been done with the image. Is there a way to find that out by looking at some values? A atmospheric correction was ...
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0answers
34 views

Attribute table: Add columns from one layer to the other one (both shp types)

I have two layers, both shp type. One contains villages with all their details, the other one is a result from a point sampling tool, so two columns - population density and elevation. What I would ...
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0answers
25 views

How to add points to points in polygon function [duplicate]

I have downloaded my shp. file and also a csv file with the population of each location. Each population is associated to a meshblock (district) that has coordinates. I need to put this population ...
0
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1answer
56 views

Problems with saving my QGIS-Project

It doesn't matter how I save my project (Qconsolidate-Plugin, Relocator-Plugin, QPackage-Plugin or manual), the output is always defective: The export always consists (as shown in the picture) of ...
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0answers
28 views

Splitting polygons (fishnetting) for improved performance?

I have been asked to develop a program to split polygons into smaller polygons to improve drawing speed in ArcGIS/QGis. While this is fairly simple, I am questioning the reasoning behind this? To ...
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0answers
45 views

How can I save my QGIS-project [duplicate]

i have a very simple question regarding my QGIS-project: How can I save it, so that other students can open it on another computer without any problems? I created the following project with eight ...
0
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0answers
35 views

Zoom to a subfile/ calc the extent of a section of a VRT in QGIS

I want to write a plugin in QGIS, which first creates a VRT from TIFs in a directory with gdalbuildvrt . Later my plugin will get a parameter, a name of a subfile of this vrt. Now I wonder how to ...
4
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1answer
59 views

Plugin not available : point sampling tool

I installed the QGIS Standalone Installer Version 2.14 (64bit). I created a map in the program called QGIS Desktop 2.14.3 with GRASS 7.0.4. I need one tool from Plugin : Point sampling tool. The ...
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0answers
26 views

How to write plugin to QGIS Composer?

I would like to write a plugin that will (hopefully) improve the QGIS Composer export to SVG (to begin with - to keep layers' names). I didn't find any QGIS Composer, and i wonder if it even possible....
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0answers
19 views

Crayfish installation library error

I have just tried to install Crayfish into QGIS and get the following message: "Crayfish Viewer depends on a platform specific compiled library which was not found. A library for your platform could ...
1
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0answers
50 views

How to select only some of the polygons from a Shapefile [closed]

I have a Shapefile containing many polygons. I need to filter and save only part of them in another Shapefile. How can I do this using QGIS?
1
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0answers
64 views

How to create cost maps based on OSM (landuse/…)?

I'd like to create cost maps (georef raster) for cross-country hiking based on OSM from pgsql/postgis plus height data. Maybe by creating multiple raster-files and the later merging them (lake=...
3
votes
2answers
211 views

Automatic selection of pixels, from a raster series, greater than minimum image of the series

Given a series of rasters, and the raster image of the minimum values of the series, I am looking for a python script capable of selecting, for each raster, the pixels whose values are greater than ...
2
votes
1answer
70 views

How can I select points within a part of a raster?

I have a map with huge amount of points (9562 villages) and two rasters: population density and land elevation. I am trying, without success for the moment, to select just those villages with high ...
1
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0answers
39 views

Line width proportional to value in attribute table in QGIS

I am visualizing trade flows in QGIS. I am trying to make the line width of approximately 100 polylines be proportional to the associated value listed for each in the attribute table. Several posts ...
2
votes
0answers
37 views

Getting underlying layer data in entry form

We have a requirement to place a point feature on a line feature (a road) in QGIS. When placing the point, we would like the road number from the line feature to be automatically populated in the ...
1
vote
0answers
52 views

Transforming polygons centroids in order to make hexbin map in QGIS? [closed]

I want to make a hexbin map of a particular kind. Hexbins can be used to embrace several points in the same area, like in this example : With this method, a large city can be covered by one hexagon,...
2
votes
0answers
113 views

QGIS - Semi-Automatic Classification Plugin v.4.9.5 - When trying to create ROI getting Error[43]: Attribute table error

when I try to create a ROI within the Plugin: Semi-Automatic Classification Plugin, I am getting the Error: Attribute table error. Which means it is not creating MC ID / MC Info or C ID / C Info in ...