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

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57 views

Is it possible to run Points2one in batch mode?

Is it possible to run Points2one in batch mode (using Qgis 2.8.1 on Unbuntu 12.04)? Basically I have 85 separate point layers and I want to create polygons using Points2one for each layer.
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1answer
217 views

How to suppress advanced digitizing tool window

I'm using QGis for years but suddenly I stuck with something that I'm sure it's an easy fix. Every time I start to create a new feature, the Advanced Digitizing tool window pops up. Do you know how to ...
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0answers
66 views

Sophisticated generation and calculation of Vector entities from Raster Data?

The first image below is shown a raster wish represents the altitude value. I created this raster by applying this process, bu using this process we can manually select an upper and lower area (so 2 ...
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1answer
227 views

When saving a .qgs file in QGIS, another appears. Is this a backup?

When saving a project file (.qgs), which when executed is automatically loaded with qgis.bat, there's another .qgs file which appears in the same directory of the original project file, although this ...
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1answer
152 views

Debug QGIS crash on Windows 7 - how?

I'm developing a QGIS plugin, and under certain circumstances, it causes QGIS itself to crash. How can I debug this, given that I am on Windows 7? I've tried using the QGIS nightly dev build (which ...
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0answers
135 views

QGIS 2.8 (openSuse 13.1) pdf export with print composer not working

I'm using QGIS 2.8 with a openSuse 13.1 system. If I try to export a map (with openlayers-plugin active) with 120 dpi it works fine, but if I change the dpi setting to something higher (like 130 dpi) ...
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0answers
156 views

Joining shapefiles based on FID in QGIS [closed]

I want to join shapefiles (or a shapefile and a data file) based on their mutual FIDs and can't see the FID in the "Target Field" dropdown on the join form. I believe this is a basic need to have ...
2
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1answer
62 views

Extracting area from DEM Raster?

After applying constraints to the DEM I polygonised the raster (using GRASS r.to.vect.area) The result is shown below with a lot of vector with resolution = [30 * 30] Is there any solution to make ...
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36 views

Programatically export map clusters in QGIS

I'm trying to export each microcluster of a large map into a composed map that shows the ff on an A4 sheet: 1) Cluster/grid box of the map 2) Larger index map with the pertinent region highlighted ...
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1answer
83 views

GPX-Tracks are not displayed correctly by many applications/web applications

I have a problem regarding GPX tracks that were created from Shapefiles using QGIS. The shapefiles were created by selecting all parts of a route from a PostGIS database. The polylines were merged ...
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1answer
110 views

Problem to create composer with open layer plugin in QGIS

Creating layout in composer I am facing a problem of dislocation of shp file and google earth image ( which I am using from "open layer plugin") Version 2.4.0 Chugiak (Mac) In the first image shows ...
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1answer
211 views

Error 4 in rasterizing a polygon shapefile

I'm using QGIS Wien 2.8.1 trying to convert a polygon shapefile to a raster, but I get the following error in a qgis-bin pop-up: ERROR 4: `' does not exist in the file system, and is not recognised ...
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0answers
154 views

QGIS - Polygon to Lines Tool Incredibly Slow

I am trying to convert a few polygons to polylines so I can save them as a .GPX file. I'm using QGIS 2.8.1 (Wein) on the Mac. It seems to be hanging. I only have a few small polygons (see screenshot)...
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0answers
51 views

OSM in Qgis 2.8 [duplicate]

The plugin 'OpenLayers plugins' doesn't work any more in Qgis version 2.8 'Wien'. Is there another solution to load/ add an open street map file?
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1answer
1k views

Can we create topographical map of private land using GPS elevation data?

Is there a way to create a relatively precise topographical map of a private land using GPS elevation data? As the land is a little bit over 100,000 square meters, the available regional topographical ...
3
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2answers
210 views

Select by expression functions in QGIS 2.8.2 (Windows)?

Please forgive me if this is obvious, but having opened a newly installed version of QGIS on Windows, I can't seem to see the list of functions normally present (as shown in the Mac image) in the '...
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0answers
35 views

Discrepancy between importing same data from CSV and GPS [closed]

I have been importing similar data by using two different methods: Entering the coordinates manually in excel and save as CSV, then importing in QGIS through delimited text layer. Column A is name, ...
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1answer
61 views

Merge 2 Pointlayers with same coordinates but different attributes in QGIS?

I have two layers with points who have exactly the same coordinates but different attribute fields. I would like to merge the tow layers so that I only have one point at each location who has the ...
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1answer
75 views

Projection change in QGIS after import & export in Grass

I'm working on an application written with Grass command in python and I have a projection problem. First I create a location with belgian lambert 72 (EPSG:31370) in Grass 7.0. After importing all ...
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0answers
189 views

Is it possible to create Isochrones in QGIS GUI?

I'm new to QGIS and have tried to create isochrones around points for quite some time. Is there any option to create isochrones on the GUI in QGIS? I know how to create them using pgAdmin (using eg ...
9
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2answers
284 views

How to ST_Split features in one table by features in another?

I need to split polygons (layer 'pol') by both closed and non-closed linestrings (layer 'lin'). Unfortunately I don't get proper results running the following query. CREATE VIEW splitted_pol AS ...
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1answer
95 views

How to reuse a layout in the QGIS print composer layout on different pages?

I've got a map template that I've created in the QGIS print composer on page 1. It includes various objects like text boxes, images (north arrow), scalebar and legend. I want to use the same template ...
2
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1answer
87 views

Is there a way to improve the time for opening a QGIS project?

We have a QGIS project using postgresql database "made with" osm2pgsql. The database is about 68GB. Our Configuration is : AMD-FX 8 cores @ 4.7Ghz 32 Gb RAM 500 Gb SSD (read/write 600Mb/s) Ubuntu 14....
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1answer
104 views

How to control the priority of individual feature labels in one layer?

I have a group of city in a small area with labels. Due to label engine it shows them in a 'random order' (and certainly optimizing) according the space the have. There is a way, without duplicate ...
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2answers
155 views

What is the easiest way to install a really old Nightly Build of QGIS Master (in Windows)?

I would like to test which nightly build between QGIS 1.8 and 2.0 caused a certain change in QGIS behavior. I know that there are very convenient exe files of weekly builds available on http://qgis....
3
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1answer
463 views

How do I set up the R Script folder in QGIS 2.8.1 Processing Toolbox (Advanced Interface)?

I am currently lacking the R Script folder in my processing toolbox under the advanced interface tab. I suspect this could be a result of the firewall in my company's wifi. I already have R ...
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1answer
65 views

Spatialite ST_area(geom) won't compute for GeomObject

I extracted a dataset from Wikimapia via API using .kml download --> ogr2ogr .kml to GML -explodecollections --> GML to .shp only LINESTRING part of geometry collection. Running QSpatiatlie in QGIS, ...
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2answers
100 views

How to combine/merge *.lul files to shape format?

I got multiple files, say 2500, I never heard about lul files before. anyway I visualised it in QGIS after number of attempt in Autocad map 3d and ArcGIS. it is basically like Basemap:Road,parcels, ...
2
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1answer
247 views

How to convert GDA eastings/northings to WGS84 lat/long in QGIS

I'm using QGIS to map weed locations and have a mixture of data from GPS, shape files of contours, OSM all in a project with CRS WGS84 (lat, long). I am trying to add in a shape file I have been given ...
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1answer
71 views

Can QGIS manage non-spatial PostgreSQL database?

I have a database with a table with plots. This table has spatial field for the area. Also, I have another table with owners. An owner can own some plots, and the there are a "id_owner" field in the ...
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3answers
394 views

Extracting difference between two massive shapefiles using QGIS?

I have two massive shapefiles and I need to create a difference shapefile output between the two. I have a layer where I have satellite coverage (orange) and then a layer where I have high resolution ...
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0answers
687 views

Export to shapefile error in QGIS from POSTGIS table

I am attempting to export a postGIS layer to a shapefile in QGIS 2.6.1 Brighton. The table has 244,674 rows. The data displays perfectly well in QGIS but when I attempt to export to shapefile I get ...
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2answers
2k views

Can QGIS export Geospatial PDF for Avenza PDF map app?

Since QGIS uses GDAL, does any map exported as a PDF become a Geospatial PDF? I am hoping to import maps from QGIS into the Avenza PDF Map app on my phone. Previous posts mentioned exporting as ...
2
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1answer
592 views

Missing processing menu in QGIS?

I'm sure there is a really simple explanation to this but haven't found any pointers on this forum or elsewhere. I seem to have lost the 'processing' menu from QGIS and can't figure out how/why!? Any ...
3
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2answers
473 views

How to create multiple QGIS layers from multiple text files?

I have a few hundred txt files (each representing a line of a river bed profile) that I need to load as (point-) layers in QGIS. Partial example: 4504764.8331;5374251.3024;397.8871;2 4504764.7761;...
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1answer
142 views

QGIS problem calculating area

I have a problem with qgis 2.8.1 (Wien). Whenever I change the project SRC to WGS84-World Mercator (EPSG 3395), the area is calculated as zero. How can I solve this problem? Is this a known bug? The ...
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2answers
265 views

How to automate specific workflow best (QGIS 2.8)?

For a project of mine, I'd like to solve a spatial analysis using QGIS. Until now, I have never automated anything GIS-related except for some rather easy steps in ArcGIS using the model builder, so ...
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2answers
46 views

add polygon to layer from text file [closed]

I am completely new to Qgis and to gis in general. I have start to work my way through the documentation but have a question that I can not find a answer to. When looking into the documentation ...
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1answer
460 views

How to round pixel values of a raster in QGIS?

I have a raster with float number values for example: 2.544459104537964 and I want to round these up to intergers. I have seen other posts on ArcGIS like this one but when I use Raster Calculator in ...
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1answer
179 views

QGIS downsample then upsample raster

I'm trying to downsample a raster then upsample it again. I am using the gdalwarp function in QGIS. When downsampling the raster looks OK in the front end, I set the cell size to 10x the original ...
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0answers
45 views

distance() function in field calculator gives unexpected results

I have two layers both containing points - each point in the first layer has a corresponding point in the second layer (same primary key). One layer has CRS EPSG:27700 and the other layer has EPSG:...
2
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0answers
94 views

QGIS: Not updating the row number properly. Attributing the last created point with “1” & vice versa

We have to capture the sample points in survey maps. While doing so, we are facing a peculiar problem. Our survey points start from left to right <- along the survey lines. Once we have captured ...
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1answer
40 views

QGIS Scalebar Font Outline

Is there a way to add a text buffer or stroke the text on the scale bar? Its impossible to read the scale when its set on a map with dark colours.
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2answers
99 views

How to update a bulk selection of fields using field calculator in QGIS 2.8.1

I have an attribute table showing vegetation communities. The table has three columns ("ID", "Veg Comm" and "Area_ha". Instead of having to copy and paste text after each polygon created into each ...
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2answers
218 views

Can't import certain tables from SQL Server to QGIS

This is a list of 193 zip codes and their geometries that do not import in QGIS. This is a list of 999 Census Block Groups and their geometries that do import in QGIS. This is the Add MSSQL Layer ...
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1answer
128 views

How to have newly added lines split existing lines where they intersect, using QGIS

I have a line shapefile where the lines form a closed polygon. Using QGIS (2.8 on OSX 10.7) I would like to add lines to the layer, basically splitting the polygon into quadrants. Then, I will need ...
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1answer
53 views

Why can't I paste coordinates in “Enter Map Coordinates”?

Using QGIS 2.6.1-Brighton, I am attempting to use the Georeferencer. My data is from NGS datasheets. I copied and pasted the data into a text document. In the "Enter Map Coordinates" dialogue, when I ...
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1answer
82 views

Why slope tiff image produced with QGIS does not show properly in paint?

So I have this slope tiff image that I created using a DEM reprojected in meters. When I view it in QGIS, it shows fine. If I try to edit the picture in paint or Gimp afterwards, I dont see the same ...
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1answer
136 views

QGIS crash when using args=0 with qgsfunction

I am trying to define a custom function in QGIS 2.8.1 that takes no arguments. from qgis.core import * from qgis.gui import * @qgsfunction(args=0, group='Custom') def test(value1, feature, parent): ...
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1answer
159 views

Plugin Red layer can not active in QGIS ver.2.8.1

I am trying to use the new plugin Red Layer, I have installed it in QGIS ver. 2.81. I can open the menu but it is not active. How do I enable it?