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

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2
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1answer
66 views

Is it possible to create Rule-Based Styling with $geometry intersecting a second layer?

I am trying to create a rule-based style based on geometries from another layer. I have found an example that does exactly what I want, except that it uses a geometry from WKT: intersects( ...
2
votes
0answers
186 views

qgis-2.2.0 database tab missing

I have recently installed QGIS-2.2.0 but the Database tab in the top-menu bar is missing. It looks the main reason is missing libgdal1h library. But when I am installing it, it's removing ...
2
votes
2answers
611 views

How to enable multithreaded processing in qgis 2.2

I have found multiple links that appear to say that this now exists in qgis 2.2, but it appears that it's only using one core to full capacity. This is running on Ubuntu 14.04 The current process is ...
2
votes
1answer
96 views

How to change attributes with QGIS python?

I have this piece of code which I would like to use for inserting values into column. It does not throw an error, the changes are not written to the source (shapefile). from qgis.utils import iface ...
2
votes
1answer
71 views

Valid values of mollweide projection in QGis

i just imported a vectorlayer (without any reference points) to qgis as mollweide projection to save it to longlat. What i am wondering about is a mathematical problem: Not every x,y coordinate on the ...
2
votes
1answer
232 views

Problem installing QGIS Valmeira on Windows 7 Professional 64-bit

I have been having trouble installing QGIS Valmeira on Windows 7 Professional with SP1. When I installed to the default directory C:\Program Files\QGIS Valmiera\, many of the predefined coordinate ...
2
votes
1answer
107 views

Can you create a CRS of superseded NSW Datum

I want to use a superseded projection (NSW integrated survey datum - referred to as ISG) because my main client utilises it. The projection is based on AGD66. We regularly receive survey files in this ...
2
votes
1answer
240 views

QGIS html annotation relative paths

I find the QGIS html annotation tool is very useful for quickly accessing a combination of key data attributes and photos. I am having trouble using relative paths for images. This doesn't work: ...
2
votes
3answers
1k views

QGIS Desktop 2.2.0 - program does not start

I just installed QGIS 2.2 (I download QGIS Standalone InstalleVersion 2.2 (32 bit)).Installation was successful without any errors. Then I try lunch QGIS Desktop 2.2.0 but the program does not start. ...
2
votes
2answers
440 views

Conversion of Latitude/Longitude to different map projection

I have two m*n matrices coming from a WRF-ARW simulation: one exclusively with longitude values and one with only latitude values. For both matrices I know the originatin projection (lambert conic ...
2
votes
1answer
59 views

Identify geographic location to points

I am quite new in QGIS and I really need your help. I have a map of Kenya divided into 68 districts and I have coordinates of 30.000 schools. The points have one variable besides the latitude and ...
2
votes
2answers
335 views

How to produce a CSV file from .tif file with elevation data? [duplicate]

just want to ask, I have a .tif file that contains all the elevation of a country. How can I convert that to a CSV file that contains x,y,z values where x and y are the latitude longitude respectively ...
2
votes
1answer
110 views

How to properly establish a PostgreSQL connection using QgsCredentials

I'm trying to establish a Postgres connection using QgsCredentials as described here: How to access user credentials in database connection? The only problem is that I cannot establish a working ...
2
votes
1answer
141 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 ...
2
votes
1answer
370 views

QGIS 2.0 Plugin: Select and Identify a Single Feature

given is a layer with some nodes on it and every node has some attributes(name, id, etc...). For showing up the informations of a single node I can use the "Identify Feature Tool". Choose the tool, ...
2
votes
3answers
305 views

Why are some points in my PostGIS layer not displayed?

I have PostGIS table with some points and various attributes. Yesterday I added some more points to the table and now weird things are happening when I try and display layers built from these points. ...
2
votes
0answers
64 views

Distribute QGis plugin which depends on certain Python packages

I developed a plugin for Qgis which depends on some Python packages. On Linux and Mac, this is not really a problem because I can easily install them with the system pip command. Windows is another ...
2
votes
3answers
495 views

How to remove vertices or lines within a polygon?

I have transformed a *.dxf-file into a polygon shape-file. In many of the polygons i have lines whicht do not belong there but i can not delete them as i normally delete vertices on polygons by ...
2
votes
4answers
486 views

Merge large number of polygons using QGIS

I have a series of polygons that are the output of another GIS program - I need to merge the polygons into a single polygon. I have tried a couple of different methods with no luck. I have tried to ...
2
votes
1answer
910 views

How to pick the coefficient in Inverse Distance Weighted method?

I'm using QGIS 1.8.0 to interpolate weather data. This is, I have a weather station located in say, A and C. With the Inverted Distance Weighting or Triangular Interpolation methods, I can ...
2
votes
1answer
97 views

Is there no editmode for CSV files? [duplicate]

I load a delimited text layer and it get's visuialized. Unfortunatly I don't know why I can't switch to edit mode. I already worked with similar .CSV files in edit mode before, under the same setup :( ...
2
votes
1answer
464 views

How to label vector features programmatically?

I am using python for QGIS 2.0.1 and I have a vector layer of points representing the positions of state labels. I want to display the 'state abbreviation' attribute on the corresponding point for ...
2
votes
1answer
1k views

Configure Orfeo Toolbox to work with QGIS v2 Windows 7 from standalone installer

I have asked this question on the QGIS mailing list, but have not yet had a satisfactory result. The QGIS manual at http://www.qgis.org/en/docs/user_manual/processing/3rdParty.html is confusing about ...
2
votes
1answer
153 views

Why do area measurements from “measure area” tool and field calculator differ?

My problem is when using the "measure Area" tool on the toolbar I get the correct value but when using the field calculator in the Layer Attributes the area is very different including -ve areas. ...
2
votes
1answer
119 views

Reprojecting Natural Earth dataset to World Eckert I

My question is connected with QGIS 2. Could anybody explain me how I ought to reproject the Natural Earth dataset there in order my world map to look correctly? When I strive to reproject these data I ...
2
votes
1answer
342 views

pyQgis in stand alone script, vector loading error

I am trying to use the Qgis functions in a stand alone Python script. I m running Mountain Lion OS, 2.7 Python & the Qgis 2.0.1 Dufour. My main problem is that I cannot get started - I cannot ...
2
votes
1answer
1k views

Is it possible to create and run custom R scripts in QGIS 2.0?

I am new to QGIS and most of the tutorials I have found are for 1.x and the overhaul has me confused. I would like to create R scripts and run them in QGIS. I have read here that it's possible using ...
2
votes
1answer
117 views

Problem converting coordinates

I'm trying to convert punctual values from lat/long to EPSG:6372, a projection for Mexico, defined by the Instituto Nacional de Estadística y Geografía (INEGI). I found a converter online but somehow ...
2
votes
0answers
180 views

Our best table-analysis with GIS? [closed]

Sometimes I think about possible analysis using GIS models (I use QGIS 1.8), and I always think about few types of visualization techniques: demographics, traffic flows, distance ones... Thanks to ...
2
votes
1answer
234 views

How can I lock the scale when panning?

I'm just wondering if there's any way to easily lock the map scale when panning etc. For example, suppose I set the scale to 1:100,000 - panning with the mouse will then alter that slightly, which can ...
2
votes
1answer
334 views

QGIS 2.0 - 2.4: Color Ramps Missing?

Since QGIS 2.0.1 the default color ramps and styling symbols seem to disappear for some users. For me, this started with QGIS 2.0.1 and still consists with 2.4. I can neither choose Smybols when ...
2
votes
1answer
166 views

How to delete points which are close to each other?

I have a vector file containing thousands of points. Where points are within x distance from each other, I wish to delete one of the points and keep the other (either by snapping to one point, or ...
2
votes
1answer
302 views

Problem with georeferencer in Qgis 2 64bit installation

I tried to use the georeferencer in the new Qgis 2 64 bits for windows. I tried with the standallone installer and with the OSgeo4w installer. The problem is when I load the raster that I want to ...
2
votes
2answers
977 views

QGIS: when using composer to save as image the image has a shift of about 50m [duplicate]

im using qgis 1.8.0; i have two layers turned on, 1 the google earth hybrid layer from the open layers plugin and a shapefile of my own making. i set on the fly projection and everything looks spot ...
2
votes
1answer
349 views

Sextante in Qgis 1.9 alpha on Ubuntu can't find saga gis 2.1

I am using Qgis 1.9 on Ubuntu 13.04, Sextante is a core part of qgis now. I am trying to access the SAGA 2.1 libraries through qgis and I keep getting a popup window that says SAGA is not installed. I ...
2
votes
2answers
387 views

Import Points with WKB format to QGIS

I have a .csv file with population data according to specific locations (Points). My problem is that all locations are given in WKB format like that: ...
2
votes
2answers
1k views

Are there only two methods of interpolation in QGIS?

I did recently a map of maximum temperature for specific area in Quantum GIS 1.8.0 and its interpolation. However, I was wondering if there are only two method of interpolation, apart from ...
2
votes
2answers
235 views

Why does the buffer take up whole screen?

I am trying to create buffers around the Hurricane Sandy path I created in QGIS (points are lat/long). I have both points from each day she was tracted and the line I created from it with Points2One. ...
2
votes
1answer
177 views

QGIS custom form: 'dynamic' default value

I am trying to make a custom form in QGIS to smoothen the digitizing process. For this purpose, I put the Edit widget (Layer properties, fields) of one of the fields on 'value map', and I loaded a ...
2
votes
2answers
786 views

Merge lines with the same 'name' attribute on QGIS?

I have a shapefile with a few thousand lines, each is a street segment. I'd like to merge all features with the same 'streetName' attribute into a single attribute. I only really care about the name ...
2
votes
1answer
489 views

How to align (georeference) images using QGIS?

I'm completely new to all this. I'm trying to make a map of Han dynasty-era China for a mod for a game called Crusader Kings 2. I've downloaded QGIS and Natural Earth 2, but I need this image to ...
2
votes
1answer
745 views

Fetch Python Plugins missing

I'm running QGis master v1.9.0 on xubuntu and the 'fetch python plugins' option is absent. This guy had this problem with vanilla 1.7.5 but fixed it by upgrading to 1.9.0 master. Nishant had this ...
2
votes
2answers
2k views

Setting “R Folder” Path in QGIS Sextante

I have installed R via the R-Project website. I have QGIS installed via OSGEO4W (currently 1.9.0 Master), and have Sextante plugin installed and working with GRASS and SAGA providers. I am now trying ...
2
votes
1answer
457 views

How to perform a cascaded combine from python script in QGIS?

I'm working with a large dataset, and I need to be able to combine up to 400,000 polygons. I have been using the QgsGeometry::combine(QgsGeometry* geometry) function and simply looping over all ...
2
votes
0answers
1k views

QGIS: After performing a table join, all the fields are “NULL”

Within QGIS, I joined .dbf table containing population data to a shapefile of Census tracts. The join field is called GISJOIN in both the target table and the shapefile's table, and this attribute ...
2
votes
2answers
360 views

How can I create a legend with the new data defined symbols functionality?

I have a large geology data set that I need to display using an industry standard set of symbols and colours. The symbols and colours are attributes of the data. I have been using the data defined ...
2
votes
1answer
534 views

Can I view the Geoserver zoom level in QGIS

I am creating some sld's using QGIS for use in Geoserver and wanted to view the current zoom level so that I can then define it in the zoom level. Is this possible? For example <!-- Local ...
2
votes
1answer
794 views

How to open *.aux file in QGIS?

My university desires to switch from using ArcGIS to using QGIS and therefore I have to figure out whether the exercises that are used in lectures can be performed using QGIS. I have an .AUX file ...
2
votes
0answers
460 views

How to write vector layer to csv file with geometry by PYTHON?

I use Python try to write vector layer file to csv file with this code QgsVectorFileWriter.writeAsVectorFormat(mylayer, r'c:\temp\xyz.csv', "utf-8", None, "CSV") It can export to xyz.csv but only ...
2
votes
2answers
100 views

Digitized Shapefile manually using wrong projection: how to fix it?

I have a raster in correct projection. I used shapefiles, and marked objects (manually), but I found out that my vector layers have different projection, so they have different size and position. Is ...