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

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118 views

How to get a pop up in QGIS when clicking on points on a map

I have QGIS V 2.12.0 and am an absolute novice, doing some volunteer work for a charity. I have created a map with added Delimited Text Layer. This references Buildings by Latitude and Longitude ...
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65 views

PostGIS Raster performances

I ingested two Landsat images into PostGIS database using : raster2pgsql -I -C -s 28356 -M -t 100x100 LS7_20150425_B40.tif public.red | psql -d postgres -U postgres raster2pgsql -I -C -s 28356 -M -t ...
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79 views

Using raster2pgsql to display data in QGIS

I am quite new to this process (using raster data in PostGIS) and tried to find some tips/solutions on other threads but I didn't manage to get things working. I ingested some Landsat data into my ...
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31 views

converting vector points to lines using QGIS 2.8 [closed]

I have about 350k of vector points that represent parking spaces, I need these points to be converted to lines and connected to the nearest point available. I've tried the point2one plugin, but ...
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44 views

How to set color of single features with Python

I have a layer with cities. I want to set a different color for a specific country. I can iterate through all cites (features) and change the color of ALL features but not only of single ones. How can ...
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40 views

Layers being lost in QGIS

Does anyone know why layers would continually be lost from a project and refuse to reload even though the project is regularly saved?
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81 views

Convert a .tif raster in .img format in QGIS

I have a raster file in .tif format and I want to convert it to .img with QGIS. Does anyone know how I could do that?
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22 views

QGIS 2.8 Change Colour of Selected features [duplicate]

How can I change the colour of the selected features in QGIS. The light yellow is not easy to see.
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32 views

Right min/max values in single band color of an asc file and resulted profile

I'm using some asc files that covered the surface of an island; every file, when it's been imported, has a different min/max values in the single band color, which is the right? How can I understand ...
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42 views

QgsExpression to apply on feature

I am using QGIS 2.8. For the documentation of QgsExpression I see the evaluate method on feature as deprecated. What am i supposed to use instead of this methods ? I have some expression and need to ...
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79 views

Applying single-band color map from file using pyQGIS?

I am importing a number of rasters using the python console in QGIS 2.8. I would like to color them all using the same color map, which I have saved to a file. I would like to do this using python so ...
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66 views

QGIS crash while delete duplicate geometry

I have a polygon shape with nearly 60 000 features (at around 3 000 square kilometres) in QGIS 2.12. I try to delete duplicate geometries from this layer and the algorithm runs until 99%. Then QGIS ...
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67 views

How to anti-alias raster data in QGIS?

How can I anti-alias the edges of raster data like in the screenshot? I tried gaussian blur, but that didn't work.
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223 views

How to run Refactor Fields algorithm in Python console?

I noticed that the Processing algorithm, Refactor Fields has a fields mapping parameter. I don't think I've come across this and definitely not used it before from the Python Console. It provides an ...
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1answer
92 views

How to select overlapping/non-overlapping polygons from a single shapfile in QGIS?

I have a shapefile with a series of polygons, some of which intersect each other and some that don't. I want to select only those that do not overlap with any other polygon. I've tried the Select by ...
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1answer
18 views

Assign values to raster in QGIS

I'm stack with a simple issue. I have a raster (DEM) and what I want to do is to assign -9999 where the pixel value of the DEM is 500 and leave all the other values as the original ones. I tried: ...
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49 views

Spline Tool does not work

In QGIS 2.12 the curves tool is integrated by default, I know. I would like to test the Spline Plugin whether it works better for my purpose or not (purpose is just to digitize streets mit nice ...
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45 views

increase resolution of generated hillshade on QGIS

I want to export a hillshade (geotiff) created from a DEM as an image for printing. But the resolution of the hillshade is way too low (900 colums, 1450 lines). Any way to upscale it? (I tried ...
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1answer
58 views

Bathymetric-topographic DEM color relief?

I am using QGIS 2.12 on a Macbook Pro running OS X 10.10.5. I have an interesting DEM for the California coast (which I downloaded from Santa Barbara, CA 1/3 arc-second MHW DEM. I've been playing ...
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69 views

How to save aliases and metadata in shapfile in Qgis

Is there a way to save the aliases in a Qgis shapefile? When I save the shapefile in a different name or open it in a different Qgis project the entered aliases are disappeard. Same for metadata. Is ...
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71 views

Spatial join multiple attributes from smaller polygons to the bigger one

I'm trying to join (to the rectangle) values from multiple polygons intersecting for this rectangle. I've tried to use some Reference functions in Field Calculator like geomintersects() but it joins ...
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2answers
52 views

How to set independent path in QgsOverlayAnalyzer >> intersection statement using Python?

How to set independent path in QgsOverlayAnalyzer >> intersection statement using Python? QgsOverlayAnalyzer.intersection(QgsVectorLayer, QgsVectorLayer, QString, bool onlySelectedFeatures=False, ...
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102 views

how can I speed up openlayers plugin for Google images in QGIS?

I use Google aerial photos when using QGIS (2.10.1) using the openlayers plugin. I find that it is very slow, and often hangs when I refresh or move around the map. Is there a way of improving its ...
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62 views

Problems with labels in QGIS 2.10

I want to label my polygons with information, and I want the labels to be in two rows - name on row 1 och volume on row 2. My problem is, that I get an extra "quare" at the end of row 1? That has ...
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76 views

QGIS shapefile to raster

I have a problem converting a shapefile to raster. I created a point-shapefile using a text-table with some xyz-coordinates. Now I want to convert it into a tiff, where all the areas without values ...
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2answers
71 views

Where is conf.py file of QGIS Training Manual?

The QGIS Training Manual, at section 1.2.3, says: "Having created your localised dataset, the final step is to replace the tokens in the conf.py file so that the appropriate names will appear in your ...
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27 views

How to Make Scripted Tools Load Output File Automatically into QGIS Project?

When writing your own scripts, and using some of the pre-fab tools how do you make the output load automatically into your QGIS project? Example: In the Help Tab of the QGIS tool ...
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61 views

Styles for Vector layers on QGIS

I'm trying to do some habitat suitability modelling on QGIS. I've downloaded several vector maps from Ordinance Survey (OS). So far I've found a Cartographic stylesheet for "OS VectorMap Local". This ...
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66 views

using qgis to split geometry in postgis: how to add unique id and copy original data in linked tables

We have set up a postgis database to manage all our old shapefiles. There is one table that contains the geometry and some basic information. There are several tables linked to that in a 1:m ...
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1answer
44 views

How to add an image to a point in QGIS?

How is it possible to add an image to a point in Qgis I was thinking about something with html and actions The following example is made by the plugin Qgis2web. But the image wouldn't show. The ...
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46 views

Qgis: QgsLogMessage.logMessage to output message in a specific tab

I am writing a Qgis plugin. I would like the plugin to write log message in a specific tab, in the Log Messages window. I tried: QgsMessageLog.logMessage("File "+ii.source()+": all pixels set to no ...
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56 views

PostGIS/QGIS: Update polygon attribute based on the mode value from a cluster of points

I'm updating a PostGIS table of polygons denoting property boundaries with some values that form part of a code for sites scattered across the properties. Neither dataset is 100% accurate so I can't ...
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28 views

Import horizontal and vertical measurements into GIS

I would like to import horizontal and vertical measurements into GIS. Basically, it is a recording of change in the stratigraphy of an archaeological site. I measured across the excavation from a ...
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71 views

Splitting a Line on a Polygon QGIS 2.10

I am currently creating a polyline shapefile and need to split a line so as to add in a new off shoot. Would anyone happen to know how to split a polyline in QGIS? I have tried the split features ...
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57 views

Coordinates for a section corner

I would like to acquire the coordinates for a specific corner of a Section. The Section is Section 12 located as part of/within Township 8 South, Range 2 West. This section is located in the ...
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54 views

Georeferenced Image Rending As Black Shape

I'm georeferencing an image in QGIS, it shows up fine on the georeferencer and goes to about the right position on the map where it's supposed to. But as you can see below, the image shows up as a ...
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1answer
62 views

How to get a list of all objects contained in my different QGis layers

I would like to know how we could do in QGis to get a list of object contained in my different opened layers: We have n .SHP files or PostgreSQL Views (they all contain at least an "object type" ...
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28 views

How can I make a polygon from intersecting lines of different layers in QGIS?

I am constructing a geological map which involves constructing boundaries to areas which vary in style across their length depending on how well defined they. To do this I have created two distinct ...
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1answer
77 views

GeoRef with QGIS from Google Earth

I thought I followed the QGIS geo-reference tutorial in precisely. The following raster (with our overlay) was snapped from GoogleEarthPro (I believe that Google Earth is using EPSG 4326, not ...
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81 views

Moving and converting virtual fields in QGIS

I have two questions about virtual fields: Is it possible to move a virtual field? I'm using Table manager to move "normal" fields but virtual fields doesn't show. Is there any simple way to ...
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194 views

QGIS 2.10.1. GRASS Algorithm Processing

While selecting the GRASS algorithms 'Processing algorithm: v.to.points - Create points along input lines' The error message came up: The specified GRASS GIS 7 folder does not contain a valid ...
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115 views

Using lasmerge in QGIS 2.8.3 is not working: “…instance has no attribute”

Every time I try running lasmerge tool from LASTools within QGIS, I get the following error message: Algorithm lasmerge starting... lasmerge instance has no attribute ...
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1answer
61 views

Distance Measure using QGIS Field Calculator?

A QGIS newbie who can't for the life of them work out the expression needed to represent distance from a point. I want to show how a walkable a neighbourhood is. I need do to this by showing what ...
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1answer
48 views

Setting draw order of labels in QGIS

We're having an issue trying to display labels UNDER a heatmap-styled layer, and can't figure out why they are always defaulting to the topmost position on the map. We're using the 'heat map' style ...
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31 views

How to update a DATE field when moving PostGIS geometry in QGIS?

I've been correcting our address point file using various methods to identify points that need to be corrected, with the final step being a manual move the point (or by the Numerical Vertex Edit) to ...
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1answer
100 views

Obtaining Centroid from Polygon in SQL Server 2008 R2

I have several spatial layers created in QGIS that are held as spatial data in SQL Server 2008 R2. What I want to do is to find the centroid (OS Easting and Northing) of the polygon from the geometry. ...
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165 views

QGIS - row/column of point in raster

Is it possible in QGIS to display column and row index of pixel in raster? I mean something similar to value tool.
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247 views

QGIS 2.10.1 GRASS Processing algorithms not working

I just did a fresh install of QGIS 2.10.1 from the qgis repos (Ubuntu 14.04). I also have grass70 installed (through ubuntugis-unstable). I can see the GRASS7 commands in the processing toolbox ...
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158 views

How to add a layer with city names into QGIS project?

I am new to GIS technologies and I wonder how to add a layer with city names to the QGIS project. I have two layers: (1) Base cartography that is a map without any labels, (2) Delimited text layer ...
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2answers
104 views

Edit Geometry with digitizing tools in QGIS of a postgis layer

I have a multiline PostGIS layer added to my QGIS 2.10.1 Pisa. I'm able to add features using the digitizing tools, but I'm not able to use the delete or node tool. It remains gray even if I'm in ...