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

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6
votes
1answer
330 views

How can I get Google Fusion Tables to work in QGIS?

I am using GDAL/OGR 1.10 and QGIS 2.0.1. I am trying to load a google fusion table into QGIS using the method mentioned in this blog post. The only difference is that I am not declaring a email and ...
1
vote
1answer
84 views

How does the tolerance influence QgsGraphBuilder and tieing of points?

I am developing a script which uses OpenStreetMap data to calculate the distance (over the road network) between each building and the nearest hospital. To do this, I mainly follow the official ...
2
votes
1answer
167 views

How do I set the projection and coordinate system for a TIFF file?

I have a topographic map of California (obtained from CAL-Atlas) as a TIFF file. I tried importing it into QGis, but it displays the map using a pixel based coordinate system rather than ...
7
votes
3answers
619 views

How to count the number of lines connected to a point?

I have a water network which and I need to install elbows and Tees (T). When 2 lines connect to a point, I want to install an elbow, when 3 lines connect, I want to install a Tee. How do I get ...
2
votes
2answers
196 views

Terrain Accessibility map using GIS (ArcGIS or QGIS)

I need to make an accessibility map showing the walking distance based on the terrain and availability of road networks, could anyone point me in the right direction where i could learn to do so. ...
1
vote
1answer
368 views

How to find the polygons bordering a feature programmatically with qgis?

Is there a way to calculate the neighbors of a polygon with pyqgis for every feature? For example, the selected polygons relative to the one in the center: I found this solution, but it's a year ...
3
votes
3answers
183 views

keeping track of edited features QGIS

Does anyone know of a way to keep track of last added or edited features in QGIS? A kind of Editor Tracking tool.
0
votes
1answer
402 views

Custom forms and Python logic: attribute error [closed]

As a beginner to Python, PyQt4, AND QGIS, I am attempting to work with the custom forms feature in QGIS. At this point I'm not sure if my error comes from the code or the .ui. This blog gave me a ...
1
vote
1answer
59 views

How to automatically add identical new polygons to a layer?

I am seeking a way, using QGIS, to automatically add polygon features identical to others on the layer. In this case, they are water valves on a water network. Anyone know of a user-friendly way to ...
4
votes
2answers
555 views

Create A Maximum-Value Composite QGIS

I am looking to create a Maximum-Value Composite raster in QGIS I have three raster images: Oct 2012 Nov 2012 Dec 2012 All are in TIFF Format, Float32, EPSG:4326 - WGS 84 I want to stack these ...
0
votes
1answer
183 views

Why doesnt QGIS show the results from a WFS BBOX from a python script

I'm trying to figure out how to do get requests in QGIS using a bbox. I can get a bbox to clip a layer when I paste my uri into a browser but the EXACT same uri returns an empty layer in QGIS. A ...
0
votes
0answers
35 views

QGIS layer only displays when I uncheck on-the-fly transformation

I have a layer that covers the stats of Indiana that has the following Layer SRS: +proj=utm +zone=16 +ellps=GRS80 +towgs84=0,0,0,0,0,0,0 +units=m +no_defs It will not display unless I uncheck the ...
3
votes
2answers
266 views

Acres calculation in QGIS

I am new to QGIS. I am creating a shapefile that will have several polygons. I need to have a column in the attribute table that will show the acres of each polygon. I have successfully done this but ...
2
votes
0answers
140 views

How can i add a north arrow in QgsComposition?

I'm trying to add an svg image of north arrow in QgsComposition using this code: mapRenderer = iface.mapCanvas().mapRenderer() theComposition = QgsComposition(mapRenderer) ...
3
votes
2answers
521 views

Creating square buffer in qgis

How can I create a buffer with square ends along a line segment in qgis? I've buffered lines using v.buffer in the GRASS plugin, but the -c option for square ends is not exposed in that interface. ...
1
vote
1answer
39 views

Plugins to guide inexperienced users: updating shapefiles and managing data

I am attempting to find a way to block adding features while certain attributes are not yet added. This would be useful in order to guide inexperienced clients and employees with the process of adding ...
0
votes
2answers
268 views

Latlng to UTM conversion with forced zone

I'm trying to convert a set of latlng coords to UTM but the points in the set are across two different UTM zones, 32T and 33T. This causes two near points like 44.51601173544275, 11.992860160820502 ...
1
vote
0answers
56 views

How to create a 1:n join and concatenate text attributes?

I have 2 polygon layers A and B. I would like to join the attributes from B into A for all the polygons from B that intersect A and for text attributes, i would like them concatenate. But apparently ...
0
votes
1answer
139 views

Automatically insert file path in QGIS table

I'm using R to create some plots that refer to specific values of some point in QGIS. Each plot is saved into a directory and for each point in QGIS I added a column with the path to the file. I know ...
0
votes
0answers
136 views

Crash when editing a layer and when saving in QGIS

When I edit the layers, and its small changes like adding a name (or make it appear in the map), QGIS very often crashes (like for every third or fourth or fifth edit, seldom gets past ten edits ...
0
votes
1answer
630 views

How to disable the Escape key for a dialog? [closed]

I may have found the solution to my own question but I have another problem. It turns out that the user can just hit "Esc" and close the form. How can I disable the escape key? I'm looking for some ...
4
votes
2answers
154 views

How to tell QGIS where to start marker line interval?

I want to tell QGIS where to start with a marker, like: use 3 markers, start at positions 0, 2, 4, and apply an interval of 12 to each marker. However, after searching for hours, I haven't found a ...
1
vote
1answer
333 views

Data exchange from Terrasync to QGIS

What method could I use to import *.ssf files from Trimble GPS as features to display in QGIS?
0
votes
1answer
81 views

Halt QGIS on startup

I have a custom made login form in Python, which launches on QGIS startup. But before the user has a chance to enter the credentials, the program starts normally, bypassing the form. From then on the ...
0
votes
1answer
78 views

Why does QGIS appear to ignore the bbox addition to my WFS uri? [closed]

I'm pulling a WFS layer from the LINZ data service (1.0.0 and 1.1.0 complient) using a python script as follows from PyQt4.QtCore import * from PyQt4.QtGui import * from qgis.core import * sourceUri ...
2
votes
1answer
1k views

How to identify line intersection in QGIS when I have more than 2 lines?

I am trying to identify where overlaps exist between multiple shapefiles. I would use the intersect tool, but it only allows me to intersect two layers. I have over one hundred individual line ...
1
vote
1answer
139 views

Python scripts of GRASS in QGIS 2.0

I want to use v.kriger from GRASS through sextante QGIS 2.0, but this command is not here. But I find, in C:\OSGeo4W\apps\grass\grass-7.0.svn\scripts, the command as a python script. How can I use ...
8
votes
2answers
1k views

How to check which version of GDAL do I have and how many?

I have installed in my computer and running the following software: PosgresSQL 9.3.2.3 PostGIS 2.1.1.1 QGIS 2.0.1 Dufour (this one installed through the OSGeo4w package) QGIS 1.7.0 Wroclaw I am ...
0
votes
1answer
109 views

How to avoid Displacement of Marker Symbols with X-Offset

I'm trying to mimick a line symbol style that is comprised of the line and 2 alternating markers. I use an interval placement of 10 units for the 'blocks' (custom svg) and 5 for points, thus every ...
8
votes
3answers
607 views

Why is using Bing Maps with QGIS free but not with ArcGIS?

Since the end of 2013 a free use of Bing Maps in ArcGIS is no longer possible. You have to obtain a Bing Maps key directly from Microsoft. In QGIS (with OpenLayers plugin) it is possible to use Bing ...
4
votes
1answer
164 views

Homogeneous vs Heterogeneous schema in Postgis

Introduction I'm working on creating a spatial database in Postgis, to be viewed and edited trough QGIS to help managing some farmland areas. One of my goals is the have a centralized place where ...
2
votes
1answer
80 views

How to use a SQL 2005 table as attribute data in QGIS

We have financial data in a SQL 2005 database which we would like to link to a cadastral shape file in QGIS. The idea is to be able to display up-to-date outstanding balances for each plot. How can we ...
2
votes
1answer
204 views

QGIS Python Labelling [closed]

i want to label a point layer with those values exceeding a set of variables attribute table as follows 'loc field'(text),'a'(float),'b'(float),'c'(float) variables as follows vara = 5, varb = 3, ...
2
votes
0answers
123 views

How to display images as cross sections in 3d

I want to display a base map and several vertical cross sections in 3D. The base map image is easy to rectify as a geotiff. How can I also display the cross sections? The cross sections are at ...
0
votes
1answer
43 views

QGIS Identify Feature tool by dragging a polygon over the datasets

When using arc, I often use the Identify features tool by clicking and dragging the tool over my data and identifying the features within it. Is there a way to do this in QGIS or is setting the ...
2
votes
1answer
38 views

Null Values After “toreal” Command

I am very new so help is greatly appreciated! I have joined a simple CSV file to my project and am attempting to change a string value to a real value. In editing mode, I bring up the field ...
2
votes
1answer
86 views

How do I limit update/insert/delete capabilities for a WMS layer in a QGIS project?

In QGIS 2.0 I have a layer based on a query to a PostgreSQL/PostGIS database and would like to serve this as a WFS layer. Users of the layer should be able to select subsets of the data based on ...
2
votes
1answer
200 views

QGIS print composer: Transparency in legend symbols

Is there a way to make the legend in the QGIS (v2.0.1) print composer reflect the same degree of transparency as set in the Style box in the main window? The legend symbol colours are shown with no ...
1
vote
1answer
130 views

How can i change vertex option programmatically using python in QGis?

I want to activate the option "Show markers only for selected features" in Setting-> options->vertex markers ,using python. does anyone know if i can do it programmatically ? i attached a photo of the ...
2
votes
1answer
200 views

How can I set a specific meter scale in the print map composer?

I am making a map for an orienteering class at the environmental education center that I work at. In order for us to easily calculate the distance between orienteering points, I need the scale to be ...
4
votes
1answer
101 views

Postgis geometry type = Geometry

Simply I've got a number of PostGIS layers that have a geometry type of Geometry, as a posed to point, line, polygon. wkb_geometry geometry(Geometry,27700) QGIS 2.0+ doesn't like this very much ...
2
votes
3answers
104 views

Determining gaps in polylines and identifying continuing sections?

Is there a relatively quick way to identify where gaps < a certain size are present between polyline? E.g. would there be an easy way to join line likes the ones in the below image if the gap was ...
1
vote
1answer
337 views

Label features on hover/click with QGIS?

Simple question: Is there a built in/easy way to show labels for features based on a hover or click action with QGIS 2.0.1?
0
votes
1answer
120 views

Installing Lecos plugin for QGis 2.0.1 on linux fedora 20

I try to install Lecos plugin, which requires python imaging library (pil), but the installation fails with the following: "you need to have the image library pil installed" I installed the ...
1
vote
1answer
410 views

Merge multiple geometry type TAB files in QGIS/OGR

I have a number of vector layers with all types of geometry (point, line/multiline, poly) and I want to combine them into a single layer in QGIS. I know MapInfo can do it but with the other 99% of my ...
0
votes
2answers
174 views

adding helicopter video files to Google Earth or QGIS

Is it possible to add a helicopter's video files to Google Earth or QGIS ? We have a flight path points derived from the xml file associated with the .mpg file which I envision being used to pilot ...
0
votes
1answer
173 views

Error using “r.los” in QGIS

I am not a "computer person". So -- I don't know what this error message means. I found this question and answer for this same problem, but the solution did not work for me, dammit. GRASS algorithm ...
5
votes
2answers
667 views

how would one get the end points of a polyline?

I am attempting to write a script to get the end points of a series polylines, and then use those end points to create a polygon. I'm not sure which tools to begin to use on this project. I would ...
0
votes
0answers
46 views

How to get tiff file of project limits at specific scale using QGIS 2.0?

I have shapefile which has a layer extent scale of 1:551920. I want the TIF file exports of the file at a scale of 1:200000. Is there way to do it automatically? Or do I have to do it manually by ...
5
votes
0answers
274 views

Printing/exporting WMTS tile layer with desired resolution / zoom level in QGIS

I have a project which uses WMTS and some vector layers in QGIS. I can freely zoom in and out, and tiles are refreshed with appropriate zoom level, just as expected. Now I would like to export part ...