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

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3
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1answer
46 views

QGIS 2.14 Debian Sid - Couldn't load plugin 'processing'

The processing plugin can't load because python import error for QtWebKit.QWebView. QGIS is installed from Debian official repositories. The plugin worked fine until 2.14.1. The error message at ...
2
votes
0answers
37 views

Aligning layers in QGIS?

I am new at QGIS and am having a problem aligning layers. Possibly I just don't understand how projection works. I have 2 layers: 1) GPS waypoints collected in a GPS UTM zone 55N 2) polygon ...
4
votes
1answer
85 views

How to load multiple vector layers into QGIS' map canvas using python scripting?

I am trying to write a standalone script in python to create a QGIS map canvas. The vector layers I am attempting to load are Shapefiles. Currently, I am able to load each vector layer, add them to ...
1
vote
1answer
60 views

Counting nodes/vertices in large polyline GeoJSON?

I have a large .geojson file (~ 1 GB) of made up of thousands of polylines. My objective is to count the number of vertices (not end points) in the entire file. Is there a python module that is ...
3
votes
1answer
48 views

Create street map with A-10 type grid & index

I need to create a printed map using QGIS with an arbitrary grid superimposed, such as is usually found on street maps.. say A to K on one axis and 1 to 10 on the other. Then I will need to create an ...
1
vote
1answer
32 views

GRASS/QGIS- “buffer” created with DEM analysis- how to avoid it?

I have, to start, a DEM raster and a shapefile, with random created points, within a given polygon. The DEM raster was clipped with that same polygon. With the DEM raster, I used GRASS to perform ...
1
vote
2answers
59 views

Are there roadmap datasets available for qgis?

On ArcGIS.com, you can download public datasets such as road maps. Do these work with qgis or are there public datasets available for qgis? By public, I'm referring to datasets that others have ...
2
votes
0answers
19 views

get active colourramp form qgis rasterlayer

I m building a pythonscript were i need the active singleband pseudocolour colourband of a raster. I want to give the active colourramp a new min and max value. I can only find examples like this ...
0
votes
2answers
46 views

how to insert Co-ordinates (LAT. and LONG.) in a map composer of QGIS 2.8

In QGIS 2.8, how to insert co-ordinates (degree, minute and second) in map composer? when I did it, the the X and Y intervals value were showing on the frame instead of actual lat. & long of the ...
0
votes
0answers
25 views

Raster to categories to shapefiles

I have a raster data file which is the population density. I would like to transfer this raster into a specific number of categories, let's say 5. After that I would like to convert the raster to a ...
2
votes
0answers
20 views

classify colourramp with new min and max value with python

For my script i want to update the existing colourramp of a raster with new min and max value. In my current code is can fill the min and max but can't classify and update the raster. How does the ...
1
vote
1answer
48 views

How to delete one band from raster file?

I was working using drone imagery (regular camera) and there is this alpha band which is preventing me from doing maximum likelihood classification. I want to remove the alpha band. So far I used ...
1
vote
0answers
48 views

KML with raster in QGIS

I have a kml file which displays correctly in Google Earth but only as a bounding box in QGIS . What can I do to see the associated raster image?
3
votes
1answer
102 views

How to make some labels BOLD using Expression Builder QGIS

I am using QGIS 2.14 and I am trying to make some of my labels bold to stand out. I'm not sure how to do this using the expression builder. I know this is wrong and I was wondering if someone could ...
3
votes
1answer
32 views

QGIS geoprocessing script, ## hand-over processing-specific information error

I have a QGIS python geoprocessing script starting like this: ## Networking = group ## lIn = vector ## lOut = output vector from qgis.core import * v = processing.getObject(lIn) #[...the rest...] ...
1
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0answers
28 views

Problem in layer overlapping (qgis)

I want to plot gps pts on qgis (version 2.14.1). I have added the vector layer of SE Asian countries, and added the delimited text layer of my gps pts which included species name, lat and lon. ...
5
votes
1answer
125 views

QGIS display on high resolution screens

I recently changed over to a laptop with a 3200x1800 resolution screen, and QGIS no longer displays properly. Many items and font are too small and almost unreadable. Slight improvements can be made ...
3
votes
0answers
28 views

Rotate feature by angle (QGIS)

Trying to offset a line by 10 degrees, rotating around an endpoint. I've read up on the older plugins and the new Rotate Feature tool, but am having trouble. I am using QGIS 2.8.9 Wien, reinstalled ...
1
vote
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 ...
1
vote
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
votes
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
votes
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
votes
1answer
66 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() ...
1
vote
1answer
31 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
votes
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 ...
0
votes
0answers
21 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 ...
1
vote
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 ...
0
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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
votes
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 ...
1
vote
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 ...
1
vote
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, ...
1
vote
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 ...
1
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0answers
52 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 ...
1
vote
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
votes
1answer
68 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....
1
vote
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). ...
0
votes
0answers
18 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
vote
1answer
25 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
votes
0answers
28 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 ...
1
vote
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
votes
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
vote
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
vote
1answer
16 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
votes
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
votes
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 ...
1
vote
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 ...
0
votes
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
votes
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
vote
1answer
36 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 ...
1
vote
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 ...