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

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92 views

Dissolving polygons with common attribute within certain proximity to each other using QGIS?

I have a land parcel with a lot of polygons with the same attribute (owners). I would like to dissolve all the polygons with the same owners but only if the polygons are within 100m of each other. How ...
1
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1answer
58 views

QGIS Categorized Symbology based on joined table

I am trying to create categorized symbology for a data layer. The column that I would like to base the categories on is a result of a table join. For some reason it isn't working. All of my polygons ...
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0answers
97 views

CRS, pixels, and floor diagram

I am trying to create a building diagram for use in a DevExpress map control. My goal is to display a raster image background in the control with a vector overlay that defines features of interest. ...
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0answers
37 views

Displaying directional bandwidths in QGIS

I have a traffic model and want to display the results in QGIS. I have a shapefile for the road network and can easily annotate the flows onto this. However, I want to display the information as ...
3
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2answers
141 views

How to access checked layers in PyQGIS?

qgis.utils.iface.activeLayer() accesses the current active layer, but I would like to get all checked layers in the QGIS ToC. How can I do it?
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0answers
96 views

How to set a print composer title from attribute table field in QGIS?

I have a point layer with several fields (pollutants values). I've created a point layer for the atlas composition (a mean coordinate point layer, 5 points, 1 for each areas). I've used a graduated ...
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0answers
221 views

How to install pygame or Tkinter for QGIS Python?

So i have downloaded pygame and installed it. Now i want to write scripts and run them through the QGIS console that implement methods of pygame but when the console reads "import pygame" i get a ...
5
votes
1answer
322 views

How do I save topology errors in QGIS?

I'm currently doing a project on finding blocked roads in a road network layer. I've figured that I can use the topology checker with the rule 'must not have dangles' and find them this way. But I ...
10
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2answers
2k views

Why are heatmaps on qgis 2.8.1 produced in the wrong CRS?

I noticed that the heatmap calculation on the new upgrade version of qgis is given the raster map without any coordinate system. Have you got the same problem?
4
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2answers
127 views

Is it possible to copy a graduated scale from a polygon to a point layer in QGIS?

I have a polygon layer (represented by cells) and a point layer. I've used the graduated symbology with the polygon layer. Now I'd like to export this graduated scale to the point layer. The field of ...
-2
votes
1answer
161 views

qgis web client only load background layers and shp file

the qgis web client only load the background layers in the helloworld map. In the natural earth i only get the shaded relief. I open the example project in QGIS Desktop and it works fine. Then i ...
3
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1answer
91 views

Memory issues with zonal statistics

I have got a memory issue due to the use of the zonal statistics command into a loop. It seems that after using the ZS command QGIS stores some information in the RAM (cache memory?). It is not ...
3
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2answers
374 views

How to digitize rectangles with snapping in QGIS?

Trying to digitize a floor plan for a building (just need polygons for each room) in QGIS (shapefile layer). I started just trying to draw the features, but want to align polygons so that there is no ...
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0answers
71 views

Labels not displaying when rendering to image with pyQGIS

I'm using the simple example in the pyQGIS cookbook http://docs.qgis.org/testing/en/docs/pyqgis_developer_cookbook/composer.html I'm able to manipulate the features in my layer using Python, but the ...
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0answers
54 views

What replaces SQLserver SqlGeometryBuilder, for Windows store apps?

Porting Visual Studio 2008 C# application to Visual Studio 2013, Windows 8.1 store\phone app (need to include DB with the application). What DB to use (coding in c#), to replace this code, not sure ...
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0answers
122 views

How do I join multiple features with a single geometry-less table entry? [duplicate]

I have three features with the same ID, let's say "5". I also have a corresponding text table containing IDs among other info (for example a "category" value). I want to join the table with the ...
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0answers
25 views

Saving and updating problems with PostGIS-Layer in QGIS

I have a OSM populated PostGIS DB (filled with osm2pgsql). All tables are working fine. But for my work, I need to combine some polygons with some points: create table attraction as select way as ...
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0answers
17 views

Installing QGIS 2.4 from tar gz file download from official QGIS website? [duplicate]

I downloaded the qgis2.4 tarball from the qgis webiste. But it doesnt follow the typical version of 3 steps to instal (1} ./configure 2} make 3} make install). So I am stuck and unable to move ...
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0answers
61 views

Parcels management and land ownership

Is it possible for me to split a feature by the column area i input?Like A feature has 3000 sqm and i have in attribute table column 1= 2000sqm and column 2= 1000 sqm and based on this 2 colums to ...
2
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0answers
223 views

ImportError: No module named gdal qgis2.8.1

i am using QGIS 2.8.1 (32 bit) in windows 7). I imported two DEMs and trying to merge (QGIS>Raster>Miscellaneous>Merge)them. Unfortunately it gives me import error as below. Traceback (most recent ...
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0answers
40 views

How to configure “-nlt MULTILINESTRING” for DXF export?

When I try and export a polygon shapefile to DXF, the resulting features in AutoCAD are hatch patterns, which is as expected if you read http://www.gdal.org/drv_dxf.html, "Polygon and MultiPolygon ...
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0answers
104 views

Interpolated raster not aligned with the vector data (QGIS)

I have loaded some tab delimited text data into QGis to interpolate the points. When I get to the interpolation (IDW) part everything breaks down. The output raster file does not align with the ...
0
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1answer
35 views

PostGIS problem finding FK to PK

I have 2 tables in a postgres db to which I need to establish a 1-m relationship between. One of the tables has geometry, the other table does not have geometry but contain fields that describe the ...
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0answers
40 views

QgsSpatialIndex crash my deploy C++ QGIS custom application on windows

When I use the QgsSpatialIndex class, after leaving the method, my application crash. Looks like the object QgsSpatialIndex class works, it brings QgsFeatureId list, but from what I noticed something ...
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0answers
91 views

Using the QGIS Graphical Modeller how can I choose specific fields to make a join based on?

I wish to join one field from a shapefile to another shapefile within the QGIS graphical modeler. I am aware that there is a 'Join attributes table' algorithm but this joins all of the fields from the ...
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2answers
399 views

How to programmatically close a QMessagebox without clicking ok or X? [closed]

So part of my script in PyQGIS is this: QMessageBox.warning(None,"Warning","bla bla bla") The box apperas just fine but i want it to close after a few seconds so i am looking for something like ...
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0answers
49 views

QGIS how to merge a linestring layer and a point layer into a multigeometry layer

I have two layers: Layer1 is point type. Layer2 is linestring type. I need to obtain one unique layer merging both layers. Of course, it will need to be multigeometry type.
3
votes
3answers
2k views

How to connect points by lines?

I have a .shp file, where I want to connect all points (approx. 100) by lines. I have a data field with the order (i.e. 1, 2, 3, ...). I have tried PointConnector and Points2One, maybe I am using ...
1
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1answer
89 views

How to copy a line from polygon to an other polygon QGIS 2.6.1

I have a polygon(state) now the state divide into two. I have a new polygon with two state. I want to copy only the new border(line) which divides the two state from new polygon to old. I am ...
1
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1answer
208 views

How to apply Zoom Extent from several QgsVector layers with Labels in PyQGIS?

I have the following case: Project constists of three layers: Open Layers plugin with Google streets QGSVector layer with Point features and Label enabled QGSVector layer with Polyline features and ...
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0answers
102 views

How to break a large map into smaller parts (tiles), for printing, in QGIS [closed]

We have a map a very wide area. We want to break it into, for example 8, mutually exclusive parts, so we can print each one separately and, if needed, put them all together and remake the whole map. ...
2
votes
1answer
439 views

How to visualize a point cloud in 3D with GRASS?

I'm new with qgis and grass so I'm sorry if there is a straightforward answer for this question but I can't seem to get it done. I've imported a pointcloud into qgis from a datafile. Now i'd like to ...
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2answers
1k views

QGIS Server 2.8 on Windows Server 2012

I'm attempting to install QGIS Server 2.8 on Windows Server 2012 R2. I've followed the instructions here and here. I've moved all the dlls from OSGeo4W to SysWOW64 for completeness' sake. I'm still ...
2
votes
1answer
47 views

Display the size of the dot based on the value [duplicate]

I import a CSV File and for each coordinate, I get a point in the map. Can I set a column for the value. Then the size should based on the value have a special size. Or based on all values, it should ...
0
votes
1answer
106 views

error in selecting data from attrribute table QGIS

First of all, im not sure why all the data points from my csv file does not show up on qgis. I enabled custom delimiters to commas and still have no clue. it worked for my other vector layers except ...
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0answers
71 views

How to reload a raster file from the python shell

I do this in the QGIS python shell: # get the raster file (and data) of the active layer canvas = qgis.utils.iface.mapCanvas() rLayer = canvas.currentLayer() rLayerPath = ...
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0answers
36 views

Can I display customer addresses based on their address?

I have a CSV file with a lot of addresses of customers. Can I import this and it display a point on the address and all other information from the CSV for this entry? I want to display later in wich ...
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0answers
34 views

How to handle Molusce ValueError: shape mismatch: objects cannot be broadcast to a single shape?

I have a problem in QGIS Molusce plugin. I opened two raster files represeting LULC of 2 years, and roads as a spatial variable. The result of geometry check was positive. On Area changes tab clicking ...
2
votes
1answer
133 views

TIN Interpolation in QGIS creates weird lines?

I am using TIN Interpolation to interpolate point features based on their cost attribute (value is between 0 and 5000). Graduated symbology creates something like this: However when I am using TIN ...
3
votes
1answer
179 views

How to change the edit widget for fields in a layer with PyQGIS?

Is possible change the edit widget with PyQGIS? I have made an extension that loads a PostGIS layer and I want to edit the date fields with the date widget by default without any change in the ...
0
votes
1answer
31 views

GRASS 7.0.0beta3 / statistics change after TIF import?

I'm new to this forum, and pretty much a beginner with GRASS (7.0.0beta3 installed atm). So my question is the following: Statistics (mean, min, max) change quite a lot after importing a .TIF grid ...
2
votes
1answer
102 views

Why does this Python script only work once on QGIS?

I have a Python script to change the color of some specific features (lines) using categories in a vector layer. When I import the script in the console, the first time through the console it works ...
1
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1answer
80 views

QGIS get the X and Y of a raster file by click

I have a raster file (Geotiff) and try to write a plugin that can change the value of one cell in a raster (== array cell). I know how to get a QGIS point but how can I get the array index from on ...
1
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1answer
69 views

non alignment of base layer and other vector layers

i'm sure you've encountered this problem repeatedly. i've tried all different methods. Enable on the fly crs transformation. go to settings and options to use crs data. go to properties and change ...
2
votes
1answer
119 views

Best practice for a group working on the same shapefile, with open source tools

We are a small (~5) group working on a single, shared shapefile. The current workflow is that each one of us does the editing on a designated attribute field, on his local copy, then exports the ...
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0answers
22 views

Older QGIS 2.4 version installation in Ubuntu 14.04 instead of QGIS 2.8 [duplicate]

Right now I am trying to run SWMM model on QGIS2.8. But the swim plugin is not compatible with 2.8 version of QGIS. Can anyone suggest me how to download and install qgis 2.4 on Ubuntu 14.04. It ...
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0answers
38 views

Unable to obtain linear distance matrix [closed]

I am using QGIS 2.6 (Brighton) and when doing a distance matrix, the output csv file appears blank. Is it possible that somehow the shapefile I am using is corrupted?Has anyone please got any hints or ...
1
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2answers
173 views

WMS not loading in QGIS 2.6.1 Brighton

I'm using QGIS 2.6.1 Brighton, trying to load the following WMS layer: http://services.nconemap.com/arcgis/services/Imagery/Orthoimagery_Latest/ImageServer/WMSServer I can successfully load the WMS ...
2
votes
0answers
367 views

Changing the background color of the Georeferencer in QGIS

Is there a way to change the background color of the Georeferencer in QGIS? What I mean is, can I somewhere change the color that does not belong to the image that is about to be georeferenced? Let’s ...
1
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1answer
110 views

Label moved with Move Label Tool disappear on QGIS v2.6.1

I have done a deep research on previous post about "move label tool", but I have not found the correct answer for my case. I have the version 2.6.1 of QGIS. When I select a particular point of my ...