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

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1answer
24 views

How to copy the geometry WKT from a temporary scratch layer in QGIS?

It seems in the 2.14.2 version of QGIS the ability to copy the WKT from the geometry of a temporary scratch layer has been removed. Previously you could create, for example, a new polygon feature in ...
4
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0answers
71 views

Convert raster to smooth contour polygons in QGIS

I have had limited success creating smooth contour polygons from a raster layers. I have created contour lines and boundary polylines and then used QGIS Union. Then I use QGIS Polygonize. Then ...
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0answers
20 views

scale polygon in Qgis [duplicate]

The task is to scale a polygon in QGIS. The procedure is performed tracing the polygon and then apply a scaling factor ( the factor used is " Distance on the ground" / " Distance on map " ) . Both ...
2
votes
1answer
111 views

How to add a Mapinfo-style text halo in QGIS print composer?

Is there any way to imitate the Mapinfo halo (of something similar) in the Print Composer. I'm trying to put some text (copyright information) over the maps and I want to make it so that it is easier ...
0
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0answers
9 views

Allocating premises between postcode polygons and telephone exchange area polygons in QGIS?

I have telephone exchange areas as one polygon layer and postcode (codepoint) polygons as another. The postcode polygons have the number of premises in each postcode as a field. I want to estimate the ...
3
votes
1answer
60 views

How to calculate correct raster stats?

I've done a lot spatial analysis in ArcGIS. Then I decided to start to learn QGIS. I started with DEM analysis. But I found differences in statistics of DEM. ArcGIS correctly recognizes the lowest and ...
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0answers
20 views

Split polygon manually- geometry validity error problem

I want to split a polygon layer manually using the Split tool in QGIS however I'm getting an error no feature slit done: The geometry is invalid. Please repair before trying to split. I have ...
-1
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1answer
41 views

Calculation of coordinates

How can I merge some small regions to create big regions? Then how would I be able to calculate the coordinates of these new regions?
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0answers
39 views

Drawing contour with python QGIS?

I have one point layer and one contour layer and I was trying to draw a line around one contour, making a circle but not a uniform one, it has to have an irregular shape. I cannot find a tool that ...
2
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0answers
39 views

Between operator QGIS

I am using QGIS Essen version (2.14.1). I am trying to filter my data based on dates. I am wondering if the "between" operator exists like in SQL? I'm trying the following query but the results are ...
2
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0answers
14 views

downloading waypoint layer from garmin gps 60CSx to QGIS 1.8.0Lisboa

I want to download waypoint from my Garmin GPS but it responded the layer GPS.gpx?type=waypoint is not a valid layer and can not be added to the map whereas my colleagues do the same without ...
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0answers
23 views

Qgis gdalogr:contour is not generating output

I am trying to use gdal:contour script in Qgis console and then script. Here is code which I tried write to console. raster = QgsRasterLayer('C:/Users/Bulva.user/Desktop/test_raster.asc', "DEM") ...
5
votes
3answers
151 views

Smoothing method for big polygons

I'm looking for an alternative to 'snakes method' for smoothing very big polygons, which I created from SRTM elevation datasets. The problem is that the smoothing is getting stuck after a while with ...
2
votes
1answer
30 views

How to connect QgsMapLayerComboBox to QgsDataDefinedButton

in Qt Designer there is the possibility to use directly QGIS custom widgets. In the UI I added a QgsMapLayerComboBox (to get the layers added in the legend) and a QgsDataDefinedButton. What I would ...
3
votes
1answer
37 views

Get QgsField alias in QGIS Python

In QGIS Python, how to get alias of field. In class QgsField, i can not find method to do this. lay = iface.activeLayer() provider = lay.dataProvider() fields = provider.getFields() for field in ...
1
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1answer
37 views

Finding nearest point using point dataset using QGIS?

I have created Geocode for some area and I couldn't find accurate Geocode's for few address. so I want to find the nearest POI for non accurated locations using accurated geocodes as referece in QGIS. ...
0
votes
1answer
31 views

Can gdalwarp reproject from ESPG:4326 (WGS84) to UTM?

I've a GeoTIFF image in ESPG:4326 (WGS84) and when I try with gdalwarp to reproject to UTM, it has problem gdalwarp -s_srs "EPSG:4326" -t_srs '+proj=utm +zone=33 +datum=WGS84 +units=m +no_defs' -of ...
3
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0answers
25 views

Inputting Layers in QGIS for PyWPS Processes

I recently downloaded the PyWPS demo files from github here: https://github.com/PyWPS/pywps-4-demo. I'm having some trouble figuring out how to use some of the processes. In particular, processes like ...
4
votes
1answer
69 views

How to randomly position coordinates within a containing feature in QGIS?

I have geocoded address data, and I am wishing to randomly position it within the census tracts that they are in to obfuscate... So the points are still within the feature but randomly move around so ...
3
votes
1answer
35 views

Performing least cost path analysis on QGIS using permeability scores for 60 points in network?

I have a map that is made up of polygons that apparently cover the whole area without leaving gaps, each representing a field, a wood, a road, a house etc. Each polygon has a score in the attributes ...
4
votes
3answers
76 views

Issues in Intersecting Voronoi Polygons With Other Boundary Shapes (QGIS)

I'm having problems in intersecting Voronoi polygons with another shape. As the image shows, I want to clip the Voronoi layer at the red costal perimeter of the UK so that the additional surface area ...
2
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1answer
38 views

Installing qgis-ltr or qgis-ltr-full with OSGeo4W or both?

I need some help with the installation of QGIS using OSGeo4W. I am using windows 7 and I want to install a 64 bit ltr release with all relevant dependencies and plugins. I choose to install qgis with ...
2
votes
1answer
42 views

How to get mean coordinates of features from a point layer?

I have a vector layer containing several points and I would like to generate the mean coordinates of these points, using QGIS only if possible. I'm looking for something similar to centroids, but for ...
2
votes
2answers
26 views

Creating a palette for categorized data displays

I regularly categorize data as follows: Prehistoric = blue Roman = red Anglo-saxon = green Medieval = yellow Post-medieval = brown Modern = grey Undated = white Is there any way to save this palette ...
3
votes
1answer
42 views

Accessing Command line options passed to QGIS exe

I am using QGIS 2.8, I am passing the raster image along with the qgis-bin.exe from the command prompt. Is there a way to access the name of the raster being passed along the exe in my plugin?
4
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0answers
62 views

Connect data from two different layers

I'm trying to connect data from two different layers to combine them in one new layer and continue working with them. Let me explain that a bit more detailed: The first layer contains data (and ...
1
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1answer
25 views

QGIS interactive gradient editor - already available?

i have found several links on the "new interactive gradient editor" - which seems pretty interesting and comfortable !!! the features shown in a youtube video are promising, but i didn't find any ...
2
votes
1answer
31 views

QGIS 2:14 - Border show-through on small Simple Markers

On small Simple Markers, 2.20000 mm or less, there is border show-through which I have been unable to eliminate with no pen or transparent border style. This is shown in the group of large and small ...
4
votes
1answer
70 views

QGIS: Batch export multiple layers to DXF

I have only had limited experience with QGIS. What i have: I currently have many different layers (water mains, sewer mains, drainage etc.). These layers are TAB files with attributed data. What i ...
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0answers
34 views

QGIS georeferenced image does not apear in the map area

I'm having issues with some georeferenced images in QGIS 2.10.1-Pisa. I generally georeference PDF's of new land subdivisions over aerial photos to get the layout of the new subdivision, generally ...
3
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0answers
40 views

QGIS 2.14: Missing list of algs in modeler (processing plugin)

I changed my QGIS-version from 2.8 to 2.14. I am very happy that v.net algs (grass7) are available now as part of the processing plugin. But now there is no list of algs inside the modeler - so no ...
1
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1answer
38 views

QGIS Lat/Long Postcodes Coordinates Being Placed Out At Sea?

I've read plenty of posts on this site regarding coordinate systems but none of them have helped solve this issue. I'm using Ordinance Survey Lat/Long coordinates for postcodes but a small number are ...
2
votes
2answers
60 views

postgis table - shapefile - mapinfo file [closed]

I have a .tab file with a ridiculous amount of columns (96). One of my colleagues at my new job wanted to update them manually one by one. I told him I could do that in an easier way using PostGIS. So ...
4
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0answers
109 views

I can't create/save changes in shape files on QGIS

I can't create or edit shapes in QGIS, the files are created on my system but cannot "fill" it with the features. I'm using QGIS 2.14.2 64bit Windows 7 This is the error i get when trying to save a ...
3
votes
1answer
46 views

Basic attribute table setup QGIS

I made several point shapefile layers. The properties only differ in their assigned colours. Each attrubute table consists of a single field "id" and each record is null. I now wish to assign a name ...
3
votes
1answer
58 views

How to Change the buffer distance from degrees to meters in QGIS 2.14 Essen?

I am new to QGIS and the whole field of GIS in general. My project and all its layers are set to the CRS of EPSG:26913, NAD83/UTM zone 13N. I am trying to use the geoprocessing tool Buffer(s) on a ...
5
votes
2answers
98 views

Subscript labels in QGIS legends

Is it possible to include subscript and superscript text in the title of a legend item in QGIS ? I have tried using <sub>some text</sub> but this just appears in the title with no change ...
3
votes
1answer
57 views

How to programmatically execute an overpass query?

I am working in QGIS using a gejson obtained from an overpass turbo query. After having defined some layer configurations and operations, I would like to update the geojson file with more up-to-date ...
3
votes
1answer
35 views

unable to render/view a postgis raster in qgis 2.14.1

I have successfully added a raster to postgis using the following: raster2pgsql -s 4326 -I -C -M 00N_030E.tif -F -t 250x250 -a test.00N_030E | psql -U postgres -d raster -h localhost -p 5432 I ...
2
votes
0answers
38 views

QGIS graphical modeler calculator

My question is about the calculator in the QGIS graphical modeler. I explain my problem issue first: I want to build a modeler that creates buffers around layers and makes a selection on a second ...
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0answers
18 views

Group location points that have a cumulative value 2000

I have a set of 400 locations (points) joined to a table having population attributes. I want to form groups of nearby locations such that the cumulative population is 2000, group can have maximum 15 ...
2
votes
1answer
35 views

How do I make a single polygon in a multi-polygon feature into a new feature?

I don't want to delete the polygon, but instead make it a new feature. There are over 100 polygons in the original feature, so 'split feature(s) parts' is not an option. None of the editing tools ...
3
votes
3answers
121 views

Statistics on classified raster overlaid with a polygon vector

I have a classified raster file and a polygon vector file. I need to overlay polygon and find out area occupied under each classification in each polygon. I am not familiar with R. Can you please ...
3
votes
2answers
43 views

How to use data from field papers to QGIS

I work on Field Papers and I need to get the information from the QR Scan code on the field papers on to QGIS. Can you please share how it can be done.
3
votes
1answer
46 views

Converting a NAD27 Lambert Conformal Conic custom projection to WGS84 using QGIS

I am trying to convert some points from NAD27 Lambert Conformal Conic (custom projection) to WGS84 using QGIS 2.8.9. I am using the datum transformation parameters for El Salvador published here: ...
1
vote
1answer
58 views

Positive Topographic Openness - do any FOSS tools (other than SAGA) provide this?

I'm looking for a FOSS GIS tool to provide Positive Topographic Openness on 32-bit Ubuntu. (which rules out ArcGIS) Normally I use SAGA GIS for this, but my Ubuntu setup is a bit messed-up after a ...
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0answers
32 views

$length calculation anomaly

A polyline layer's (green) length is being calculated via $length. Result: ~100 meters (EPSG 31466). A buffer of 5meters is created and via Voronoi Polygons (and several other steps) a centerline ...
2
votes
1answer
24 views

Get Altitude for Multiple Objects

I use QGIS and I has two layers: one with point objects (more than 1000) and one with surface (it is a version of DCW). I want compute altitude of all points. Basically, I want to get an array where ...
1
vote
1answer
20 views

Display card problem in the browser [closed]

I'm having a trouble with the extent. I don't know how to get them in QGIS and I need to display a map with two layers in a website. For this I used OpenLayers and MapServer as WMS server to serve my ...
1
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1answer
38 views

QGIS - Show count of same attribute in feature (on visible map or by same field)

In QGIS 2.14 I have a feature with two fields; Element Type (TF1, TF2, TF3, TF4) and Trail Nº (1, 2, 3, 4, 5, 6) Each Trail has multiple Elements. I.E. Trail 1 may have 6* TF1 and 2* TF2, while ...