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

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Is it possible to perform spatial join in PostGIS and keep all features?

I am attempting to create an employment change map using a hex grid. I have individual establishment data as points with attached employment figures. When I ran the spatial join using the postGIS ...
3
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1answer
25 views

QGIS Convert bathymetry shapefile from fillable to strokeable

In Java I would like to stroke the bathymetry depth lines instead of filling the area. I'm starting with the Natural Earth Bathymetric Data: ...
1
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0answers
65 views

Grass 7 no longer works via the Processing Toolbox in QGIS

When I try to execute a Grass 7 algorithm via the Processing Toolbox in QGIS 2.10, 2.8.2 or 2.8.1, I get the following error: Missing dependency. This algorithm cannot be run :-( QGIS ...
3
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0answers
21 views

How do I count the number of vector lines that pass though a given raster cell?

I am working on a project (currently in GRASS7 though I'm not against exporting to Arc or R or other software if necessary) where I am generating thousands of shortest cost paths (using the r.walk and ...
2
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0answers
22 views

Minidump Error Messages With Large Dataset

I'm using QGIS 2.8 on a system running Windows 8.1 (x64) with 12GB of RAM. I am attempting to run analyses of a very large database (.gdb format, 7.17GB). In attempting to run the "Join attributes by ...
2
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2answers
65 views

Pipeline connectivity

I'm trying to find a way to determine pipeline connections located downstream a critical facility and score how far those connections are from the facility. Any Thoughts?
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0answers
19 views

How to insert composer file name and path in QGIS print composer

Can you automatically insert the print composer name and project file path as text in print composers in QGIS (v2.8) without copying and pasting the path? e.g. equivalent functionality to inserting ...
1
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2answers
29 views

QGIS 2.2 is very slow while saving the edited layers

I am using QGIS 2.2 64 bit in windows 7 system. I have an issue while saving the layers after editing. Its taking more time to save my edits. Some times it's working fine but very often i am getting ...
1
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1answer
35 views

QGIS Composer: Force loading of all tiles on export

I face the problem that not all tiles are loaded on a map export via the QGIS composer. This happens randomly with all kinds of tile servers provided by the openlayers-plugin. Any hint how I can ...
1
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1answer
28 views

Shape Files and adding Label Data

Introduction: I'm still fairly new to GIS and have only had about 3 weeks experience. I set up an OSM server locally with .osm.pbf data and it worked just fine. When I pulled the map in the browser, ...
1
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2answers
56 views

Importing raster adf files with the additional files

I am trying to import a vegetation data raster in Esri GRID format from the USDA into QGIS. One file ("w0001.adf") can be added using "add raster", but the attribute table and other info register as ...
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0answers
20 views

QGIS models. deleting multiple columns is slow, is there a better way?

I have a process that has lots of items. This for some reason seems to make a difference to the time it takes to drop a column from a shape file during a model run. i need to drop MANY columns. QGIS ...
2
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25 views

cutting donuts in qgis

Im trying to cut donut polygons ready to go into a system that cant display them. Basically the exact opposite of this post: How to convert fake donut holes in polygons to real ones? I want to cut ...
2
votes
2answers
37 views

How to convert CSV file in VRT

Im a geomatics student. For the treatment I would like to make, I use the gdal executable in QGIS file, with a DOS command. I have a csv file like this (test.csv) : X Y -5.48 42.81 -4.78 ...
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0answers
42 views

Using GEOJSON offline in QGIS

I have some GEOJSON-Layers in my QGIS-project. The problem is, that when I zoom in or out, it takes very long to built up the window again. That's because it always loads it from the server. But I ...
1
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1answer
71 views

Big performance difference reading shapefiles between QGIS and R

I'm trying to read the belgian landuse ESRI shapefile from geofabrik.de: http://download.geofabrik.de/europe/belgium.html In QGIS it's just a matter of seconds, but in R using the readOGR function ...
3
votes
1answer
40 views

Moving cursor using PyQGIS?

I would like to move the cursor to a given x,y coordinates of the MapCanvas. Is there an easy way to do this using PyQGIS?
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0answers
26 views

Generating shapefile of polylines using pyshp from a csv file and opening file in qgis

I tried the solution posted in: Creating Polyline from GML using PyShp?, Using PyShp to convert polygons in *.csv to *.shp files? and Using PyShp to create polygon shapefiles? to generate ...
3
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0answers
45 views

How to speed up simultaneous working with PostGIS layers in QGIS?

we are working on one big layer at the same time (10-20 people). Some of us use QGIS 2.8.1 and the other 2.6. The user with 2.8 have a lot of crashes (QGIS). The 2.6 users don't have this crashes but ...
2
votes
0answers
33 views

How to create multiple polyline transects with a certain orientation?

I am attempting to create multiple polyline transects and use them as cross-section profiles to analyze snow drifts on a landscape. Is there a method of creating multiple transects in such a way that ...
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0answers
20 views

Is it possible update a shapefile instead create a new one when using Processing?

Using Processing to add or calculate a field it's always necessary create a new shapefile? Is there a way to just update and keep using same layer?
0
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0answers
13 views

QGIS Training Manual - Lesson 12.2.1 (GRASS GIS) - r.colors.table module does not color raster

I am going through the QGIS Training Manual, Lesson 12.2.1 ("Follow Along: Set Raster Colors) and noticed that the 'r.colors.table' GRASS module did not color my DEM raster layer which I imported via ...
4
votes
1answer
54 views

Grid vs. Polygon Overlay in R gives different results than in QGIS

I have a shapefile of range polygons. Each colored set of polygons represents a different group of species/genera/whatever. I next overlay a 5x5 grid onto this map. And then use join attributes by ...
0
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0answers
16 views

Converting Points to Lines in QGIS using Points2One Plugin - generates attribute table but the lines are not visible

I am using the Points2One plug in (QGIS 2.6.0) to generate lines from points. There are 2 layers on which I have worked on. Point Layer 1: This was generated/created for testing purpose with fields ...
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0answers
20 views

Accessing SD card and/or cloud storage in QGIS android

Is there anyway to access the SD card or cloud storage in QGIS for android? I find that I will be running out of space on my tablet anytime soon as it seems everything has to be on the main device ...
1
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1answer
25 views

QGIS2WEB Plugin (openLayer3) for QGIS not exporting raster images

I am using the QGIS2WEB plugin for QGIS. I have added vector features as well as a raster image (.tif or .ecw) format. When I try to export the webmap, all the layers are visible expect the rasters. ...
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0answers
14 views

How can i add sub menu under custom top menu in QGIS using python

I have added "My Tools" Menu on top. Now i am clicking on "Plugin" then selecting QGIS Plugin bulider. Here in the menu field a drop down list is coming. How can i add "My tools" in this drop down ...
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0answers
21 views

qgis unable to connect to ms sql server using sql authentication

I am getting the following error when I try to set up a connection to a MS SQL Server database using sql server authentication. I did find a bug report from 2014, but that was apparently fixed and ...
1
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1answer
24 views

Capturing coordinates via snap with QGIS

I would like to know if there is a way to get and extract the coordinates of a node (one of the node that conforms a polygon) in order to use these pair of coordinates to georeference a DXF file, ...
1
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1answer
29 views

QGIS Attribution and Geometry Query Question

I am trying to use select by expression to query lines that contain certain attributes and that there geomerty touch. In other words are connected or neighbor each other. I tried a query such as ...
3
votes
2answers
43 views

QGIS: additional description in legend [duplicate]

In ArcMap there is the possibility to have a symbol, the symbol description or layer name and an additional description in your legend Layer Properties --> Symbology --> Fetaures: Single symbol --> ...
2
votes
2answers
32 views

What CRS is the USGS Global Land Cover Characteristics Data Base?

I have trouble bringing land cover data from the USGS into a "decent" coordinate system. I obtained an .img file of the "Global Land Cover Characteristics Data Base Version 2.0" from ...
0
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1answer
28 views

PopUp with Images with QGIS2web

is it possible to create popups with images via QGIS2web? if yes, what would be the workflow? Couldn't it figure out yet. So any help is welcome! Thanks
3
votes
0answers
33 views

Extract the outer points of a Point Shape into a Line Shape? [duplicate]

I've installed QGIS 2.8.2 since a few days and have no experience with this application. I try to extract the outer points of a Point Shape into a Line Shape, like a shell for the inner points. All ...
1
vote
2answers
48 views

Topological errors after dissolve - how to avoid/get rid of?

After dissolving a layer in QGIS 2.8, I get a lot of topological errors in the new (dissolved) layer. Any suggestions as to how to get rid of these errors without manually editing each one? ...
3
votes
0answers
35 views

Trouble importing an QGIS ascii DEM file

The output I get from QGIS 7.0.1 for an ASCII DEM file doesn't seem to be a correct format. It differs from the format I get when I download a DEM file from webGIS ( ...
6
votes
2answers
225 views

Is there a way of mirroring layers on QGIS?

I would like to know if there is any way of mirroring layers on QGIS. My current project is a bit hard to explain... I'm excavating the inside of a large pot and, in the end I will have a set of plans ...
4
votes
1answer
50 views

Generate grid shapefile in R

I have the following shapefile of a 10x10 degree latitude/longitude grid that I created in QGIS. I can read it into R using the rgdal package. Grid<-readOGR(".","GridShapeFile") It has the ...
1
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0answers
42 views

QGIS printing shift on WGS 84 Pseudo Mercator base

I've had this problem before but I'm not succeeding in fixing it using what I thought worked before. This has been brought up as an issue previously, but I'm stuck when I apply the previous answers. ...
1
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0answers
40 views

Compile QGIS from source (with Grass)

I recently decided to reinstall QGIS and build against the latest version of GDAL - something I have been putting off for ages because I suspected it would be a nightmare. Lo and behold it has been, ...
2
votes
3answers
100 views

How do I upload a KML file into QGIS with the attribute data intact? It is present in Google Earth but not when imported into QGIS?

http://data.gov.uk/dataset/sites-of-biological-importance-sbi-in-greater-manchester-as-at-2015-04-28 This is the website which contains the data I need. I need to show the site names on my map, but I ...
-1
votes
2answers
51 views

What and Where are the best courses in GIS for a beginner? (Southern UK) [closed]

I use QGIS 2.8 for creating plans in my new job and would like to study how GISs work, pulling data through from databases etc. Any advice would be gratefully received.
2
votes
1answer
53 views

Processing algorithm fails from Python script

I'm trying to write a Python script performing a geoalgorithm. What is surprising me is the following: I first test the algorithm by QGIS (2.8) interface. In my case, the GRASS interpolator ...
1
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0answers
46 views

How can i add custom menu in QGIS Using python

I am tried to add a custom main menu in QGIS Desktop Application. Here I am already added custom sub menu in QGIS but I want to add a custom main menu in QGIS using Python. See the blow image.
2
votes
1answer
33 views

QGIS updated polygon areas

I'm using QGIS 2.6 and regularly update a shapefile layer to indicate felling progress. However, if I edit the nodes of a polygon, save the layer out then look at the Attributes table the area shown ...
5
votes
3answers
151 views

How to find and replace attribute values based on a list

I have a Shapefile and a list in .csv which contains two columns with names: "Old_name" which contains the old names that already exist in the attribute table of the previously mentioned Shapefile; ...
2
votes
1answer
38 views

The QGIS atlas defined with pyqgis and a QPT template exports the same maps

I need to generate an atlas for each feature from a layer for reporting. There will be created a few maps. The centre of each map must be focused on each feature. In this task I use a predefined QPT ...
5
votes
2answers
107 views

How to calculate with time values in QGIS?

I have two string fields in a vector layer, "From" and "To", with values in the format of 10:16:30 and 10:18:00 e.g. I would like to calculate the difference in minutes as a decimal value, in this ...
4
votes
1answer
153 views

Updating SRID (Update_GeometrySRID) does not alter polygons (when it should)

I am trying to change the SRID of polygons layer, but I'm having trouble visualizing the result. I the SRID is misreported the shapefile I used to import into PostGIS. The metadata says the ...
1
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0answers
41 views

Turning “normal” Vector Data into a GIS

I have a map in Adobe Illustrator with several vector layers. ( Therefore the vector data have no spatial reference and no attributes. What is the best way to turn these vector data into a GIS and ...