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

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231 views

Problem with import CSV files to QGIS 2.0.1

I have a problem with import CSV files to QGIS 2.0.1. I have a file with WGS84 coordinates it looks that: Nr;Longitude;Latitude 1;18,06,23.66;54,83,12.50 2;18,08,81.30;54,73,09.30 ...
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0answers
205 views

How to programmatically set a rule-based renderer in QGIS?

These days im in a process of developing a plugin , which highlights/change color of set of features in a vector layer depending on some calculation. i found nice article about QGIS – Rule based ...
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21 views

Why cant i buffer vector points imported from csv? [duplicate]

I ve imported a csv file with adresses of stores in longitude and latitude. I ve saved it as a shapefile and i can see the points on a map. Now i m trying to buffer the points to end up with ...
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1answer
161 views

How to select polygons by distance to a single polygon in another layer?

I have a shapefile A with a group of polygons, lakes. Now I want to select the polygons(lakes) that are within a specific distance to a polygon in a second shapefile, B, with the polygon a city. In ...
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1answer
154 views

How to install QGIS 2.0 on Ubuntu 13.10?

How can I install new version of QGIS (2.0)? When I try with the indication of the official web site of qgis, terminal write me that the last version of qgis (1.7.5 wrowclaw) has several plugins that ...
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2answers
381 views

How to get the file paths of the loaded layers in a QGIS plugin?

I am very new to GIS, QGIS and Python so please bear with me. I am using QGIS 2.0 and I would like to develop a QGIS plugin that would display the raster layers of the main window in order to allow ...
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2answers
53 views

How to get rid of artefact rectangles in QGIS Print Composer?

when inserting a map on the canvas of print composer and moving that map around, quite often, there is a rectangle that cannot be deleted. This rectangle is positioned at the initial place, where I ...
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2answers
2k views

How to perform SQL queries and get results from QGIS python console?

I'm writing a python script using QGIS API. I have to get results from postgres database table. The table has geometry field and other non-geometry fields. I want to perform SQL queries on ...
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1answer
293 views

Get geometry column back when counting points in polygon using PostGIS

I have two PostGIS tables: earthquakes and borders, which contain point data on earthquake locations, and polygons of countries in the world respectively. I want to try and count the earthquakes ...
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2answers
1k views

How to resize symbols in the QGIS Print Composer legend?

I am trying to map a count data type via graduated symbol against a chloropleth and the legend is too big. The circles of the graduated symbols are the actual size of their corresponding values in ...
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1answer
97 views

Problems with connecting QDateEdit and QTimeEdit widgets to corresponding Field in QGIS Layer (shp/spatialite)

Could anybody give me a hint how to connect the QDateEdit and the QTimeEdit widgets with a field in a QGIS layer (shp or spatialite). The fields in the QGIS layers are from datatype "date" ...
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1answer
54 views

Problem with QGIS unable to access virtual drive

After a motherboard failure I have had to reinstall QGIS Dufour on a Windows 7 laptop. As I share data with a desktop machine I use LiveDrive briefcase as a virtual drive. With all versions of QGIS I ...
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1answer
252 views

Polygonize(raster to vector) [closed]

I have been install QGIS 2.0.1.when I use Polygonize (Raster to vector)for convert jpg to shp I get error message such as: C:\windows\123.exe is not recognized as an internal or external ...
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2answers
970 views

How to limit decimal places of coordinate values in GEOJSON file using QGIS 2.0.1-Dufour

Using "QGIS 2.0.1-Dufour", I try to convert a vector layer into GEOJSON file using "Save As" sub menu. I get the GEOJSON file, but the coordinates of points have values up to 15 decimal places. How ...
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2answers
335 views

Draw great circle rays from a single point along specific directions

How can I draw great circle rays starting from a single given point P (for example, from coordinate [34 N, 116 W] in this map) and along directions D1, D2, ... (for example, 30, 45 and 135 degrees) in ...
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1answer
347 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 ...
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1answer
85 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 ...
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1answer
194 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 ...
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3answers
678 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 ...
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2answers
214 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. ...
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1answer
395 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 ...
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3answers
203 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.
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1answer
467 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 ...
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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
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2answers
636 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 ...
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1answer
197 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 ...
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0answers
36 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
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2answers
302 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 ...
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0answers
149 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
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2answers
576 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. ...
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1answer
40 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 ...
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2answers
281 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 ...
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0answers
57 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 ...
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1answer
163 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 ...
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0answers
152 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 ...
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1answer
705 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
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2answers
163 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 ...
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1answer
364 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?
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1answer
84 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 ...
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1answer
82 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 ...
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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 ...
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1answer
150 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 ...
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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
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1answer
114 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 ...
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3answers
646 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
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1answer
171 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 ...
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1answer
84 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
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1answer
216 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
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0answers
135 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 ...
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1answer
48 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 ...