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

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3
votes
3answers
75 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
vote
1answer
10 views

How to access multiple active layers?

qgis.utils.iface.activeLayer() accesses the current active layer, but what is there are multiple layers that are currently selected? How can I access both of these layers?
0
votes
0answers
6 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 ...
0
votes
0answers
6 views

Georeferencing an old map in QGIS using Thin Plate Spline

I georeferenced this old map using Thin Plate Spline, and Cubic Spline as transformation settings. However, the result was quite bad. Do I have to add points througout the whole rasterfile for this ...
2
votes
1answer
144 views

Calculate area in square meters from degrees?

I have a polygon shape file in geographic coordinate system, i would like to calculate area in square meters in QGIS using python. Is there any formula or equation to do this? Thanks
3
votes
1answer
228 views

How to buffer a point by cardinal distances to create a polygon?

I am trying to buffer a point by distances in a table to create a polygon or line for example For a point with known x,y buffer based on the following radius: North= 20m East= 21.5m South= 14m West= ...
0
votes
0answers
10 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. ...
0
votes
0answers
20 views

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

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 ...
3
votes
2answers
50 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 ...
1
vote
0answers
18 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 ...
0
votes
0answers
11 views

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 ...
0
votes
0answers
17 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 ...
0
votes
0answers
10 views

How to create custom input widget using Plugin builder?

I am trying to develop a plugin that takes in user input for the time, using the QGIS plugin builder. However, I want to specify the different times the user is allowed to select from when the plugin ...
1
vote
2answers
206 views

render geotiff tiles as a map layer

i have the following problem: i have downloaded tiff files with gMapMaker and transformed them to GeoTiff using the associated .map files in QGIS. now i want to render these GeoTiff files to use them ...
1
vote
0answers
16 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 ...
1
vote
1answer
26 views

Export graduated scale from polygon to point layer in QGIS

I'm stuck with a simple problem. 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 ...
3
votes
0answers
34 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? Gil
1
vote
1answer
181 views

QGIS Invalid object name 'geometry_columns' QODBC3:Unable to execute statement

I was using Lisboa 1.8 with SQL Express and tables with geometry. Connections were working with 1.8 and are working with ArcGIS, so I know my tables and geometry are fine. I installed 2.4 Chugiak, ...
0
votes
0answers
14 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 ...
-2
votes
1answer
27 views

qgis web client only load background layers and shp file

the qgis web client only load the background layers in the halloworld 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 ...
1
vote
1answer
27 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 ...
1
vote
1answer
43 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 ...
5
votes
1answer
157 views

Calculating a Unique ID on a Subgroup of Polygons

I would like to assign a unique ID to polygons in a dataset. The catch to my issue is that I would like polygons that fall within a polygon to have the same unique ID. My example is related to ...
1
vote
2answers
132 views

Interpolation of xyz data

Data has been given to us in a HUGE .xyz file, which has been split into many component CSV files. When I upload the CSV file, then create the shape file by "save as", all is fine. When I go to ...
-4
votes
0answers
40 views

error while trying to build QGIS-2.6.1: qgis, qgis_app, qgis_gui fails for the reason qwt class couldn't found and QtUiTools.lib linking ignored [closed]

While trying to build qgis-2.6.1 from source on windows 7 32 bit with mvc++ 2008 I got the overall result ========== Rebuild All: 281 succeeded, 3 failed, 0 skipped ========== from this I am able to ...
3
votes
1answer
132 views

How to calculate the intersected area from a layer with overlapping buffers in qgis

I need to calculate the area of landusetypes in 50m around various dots (all in one shapfile). My problem is, the buffers around the dots are overlapping each over in some places. I tried to ...
1
vote
0answers
9 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 ...
0
votes
0answers
12 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 ...
0
votes
0answers
10 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 ...
0
votes
0answers
14 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 ...
1
vote
2answers
534 views

installing older version of QGIS on Ubuntu

I recently installed the latest version of QGIS (2.0) on my UBUNTU 12.04. But am not very satisfied with it. I would like to uninstall it and reinstall QGIS 1.8 v on Ubuntu. Am unable to do so. It ...
0
votes
0answers
20 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 ...
0
votes
1answer
24 views

Tools for building and exporting high resolution geotiff

I'm having some really nice raster maps in geotiff format. I would like to add some features to these maps as well as then exporting them as tiles for serving the map from a web server. Preferably I ...
0
votes
1answer
35 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 ...
0
votes
1answer
12 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 ...
1
vote
0answers
13 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 ...
0
votes
0answers
14 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 ...
1
vote
0answers
15 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 ...
2
votes
1answer
422 views

.dxf export in QGIS 2.0.1 gives hatches instead of polylines

This may see like a stupid question, but I'm new to QGIS, so please bear with me. I'm having a problem when saving as .dxf. I export a building layer (polygons) as a .dxf file However in AutoCAD it ...
4
votes
1answer
147 views

Is there an issue with Zonal Statistics calculating wrong mean values?

I tried to solve the following issue by myself but without success. On the one hand I have a raster file which is the result of the processing "shapes to grid" tool. On the other hand I have a ...
0
votes
0answers
13 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 ...
1
vote
4answers
2k views

Free Imagery WMS Feeds in QGIS

I was wondering if anyone knows of a free WMS of imagery that I could use within QGIS. The imagery does not have to be high resolution (Blue Marble even). I would like to have a base imagery feed ...
1
vote
1answer
305 views

Why doesn't the Kernel Density Estimate function appear in AniMove plugin?

can anyone tell me why the Kernel Density Estimate function does not appear under my AniMove plugin in QGIS? I can only perform the MCP. I run Windows OS.
5
votes
4answers
900 views

Split Lines at Intersection of Other Lines

I have two line layers (roads and contours in this example) and I would like to split the roads layer every time it crosses/intersects a feature on the contour layer. I can't seem to find a tool that ...
2
votes
1answer
28 views

Identify tool and highlighting behaviour in QGIS 2.6

I have a problem with the identify tool in QGIS 2.6. Somehow the object highlighting doesn't go off when i click on another object with the identify tool in QGIS. In earlier versions, when you ...
1
vote
3answers
2k views

Where is the QGIS Parallel Line Plugin?

Somehow I believe to recall there does exist some ind of "draw paralel line" plugin for QGIS. Could anyone please point me to - I cant find it :-/
-1
votes
0answers
25 views

image popups in QGIS

after choosing a file name am supposed to use an identify tool to click on a feature and give it a name..but in my case in my school property layer there is no identify too. in this case i don not ...
1
vote
0answers
9 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 ...
0
votes
0answers
11 views

How to specify which fields to join to another feature in the QGIS Graphical Modeler

I wish to join one field from a shapefile to another shapefile within the graphical modeler. I am aware that there is a 'Join attributes table' algorithm but this joins all of the fields from the ...
1
vote
1answer
33 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 ...