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

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9
votes
0answers
716 views

How to define Winkel Tripel in proj 4.8.0?

I have QGIS with proj 4.8.0 installed. I'd like to add Winkel Tripel projection which seems to be defined as +proj=wintri But that definition string does not work. Is this a bug in my proj version, ...
6
votes
0answers
56 views

Label placement on rotated map in QGIS

I'm a newbie to GIS and QGIS (please be nice to me). I'm working on a map for a garden/arboretum catalogue using QGIS 2.6.1. The arboretum has been surveyed using GPS, and the specimen trees and ...
5
votes
0answers
89 views

How to create accurate heat maps and hot spot maps in QGIS?

I am mapping 5 heritage sites using DGPS point data. Each site has 100s, and in two cases 1000s, of points representing various attributes. I want to show the density of attributes and then ...
5
votes
0answers
281 views

ESRI Personal Geodatabases in QGIS 2.6

I am having an issue loading any ESRI personal geodatabase in QGIS 2.6. I have a number of files that worked in QGIS 2.4 and having done the upgrade I can't open them in 2.6. I have tried this with ...
5
votes
0answers
115 views

How to create a python plugin in QGIS 2.4.0?

While I am learning to create a python plugin in QGIS 2.4.0, I have followed the proceedure expalined in ...
5
votes
0answers
110 views

How to compare two sets of points in QGIS?

I have two point layers with XYZ data; one set are points measured in the field and the second set is a Lidar data set. I want to check the accuracy of the Lidar in comparison to the measured data. ...
5
votes
0answers
179 views

How to do Manhattan Voronoi on QGIS?

I've spending last two weeks trying to discover how to do a Manhattan Voronoi on QGIS. For the difference between Manhattan Voronoi and "normal" Euclidean Voronoi, please check this link Can someone ...
5
votes
0answers
138 views

Convert Graphics to Vector in QGIS

I am wondering if there is a way to convert a graphic produced from symbology in QGIS to a vector layer (ie: shapefile). I have a point layer with bearing direction in the attribute table. Following ...
5
votes
0answers
478 views

How to create a customizabe table in QGIS Print Composer?

I would like to add a custom table to a map layout created in QGIS. I would like a fair bit of control over the look of the table (borders, background colours of the cells, etc.), and it appears that ...
5
votes
0answers
431 views

PyQGIS CRS on the fly reprojetion

As a first step of a pyqgis plugin I'm trying to import several shape files at once. To get them aligned, using the GUI, I'd enable on the fly reprojections and set the project crs to WGS84. I'd then ...
5
votes
0answers
378 views

Modifying File GDB Feature Class Features Using QGIS

I've installed the File GDB API using the OSGEO4W advanced installation when installing QGIS. I've had a bit of trouble with it initially and have posted a few questions with some helpful Stack ...
5
votes
0answers
378 views

Grouping analysis of points to divide a polygon into n number of sub-regions

I'm attempting to create n sub-regions from a polygon based on a cluster analysis of a bunch of overlapping raster layers (physical layers, eg: depth, currents, waves). Briefly, I can create a ...
5
votes
0answers
617 views

How to get rpy2 for QGIS on OSX?

I am a new QGIS user, have installed QGIS on a Mac running Snow Leopard OSX 10.6.8 following all the instructions. QGIS seems to work well for everything other than when I boot up I get the message ...
4
votes
0answers
83 views

filename of current style in QGIS using Python

I get the name of the current style file using layer.styleURI(). Then, I change the style file using layer.loadNamedStyle(different_filename). However, when I call layer.styleURI() again, it returns ...
4
votes
0answers
76 views

How to submit user scripts for Processing Toolbox (QGIS 2.6)?

QGIS 2.6 change-log says that now there is some kind of repository where users can submit their scripts to make them available for everyone. Unfortunately I was unable to find any details about how to ...
4
votes
0answers
58 views

Is there a limit to the number of polygon points you can export to CSV in QGIS 2.4?

Using QGIS 2.4 I am currently importing a csv file with ~30,000 polygons (polygons in WKT format). I also have a United States shapefile. I have used the Clip function to get only the polygons that ...
4
votes
0answers
203 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 ...
4
votes
0answers
106 views

How can I create a form so the user has to be authenticated to access a project?

I have a login form in QGIS and when it is loaded, python gives me an error for, apparently, not recognizing the findchild part. This is due to the fact that the form isn't loaded before the script is ...
4
votes
0answers
159 views

How to select features based upon multiple values in graphical modeler?

I'm trying to create a basic model using QGIS, the QGIS graphical modeler and the sextante toolbar. In part of the model, I need to select features based upon multiple attribute values (for example - ...
4
votes
0answers
259 views

Weather conditions forecasting / interpolation

I'm trying to carry out weather conditions interpolations. I have information of 92 weather stations for 800,000 km2. As you can imagine the extension of land is huge and I need some kind or weather ...
4
votes
0answers
292 views

How do I install Orfeo toolbox and Qgis 1.9?

I'm having a lot of trouble getting Orfeo toolbox and Qgis 2.0 working. I followed the qgis wiki instructios, added the ppa, installed qgis 1.9 (it's beautiful, great work!). But when i tried to ...
4
votes
0answers
82 views

Is there a way to label a layer using its file name or layer name?

Is there a way to label a layer using its file name or layer name (if I'd change it in Layers window TOC)? I tried some functions but I'm not good on that. I have lots of shapes (lines) and it would ...
4
votes
0answers
1k views

How to open a ESRI geodatabase in QGIS (Ubuntu)?

So far I have found instructions on stack exchange but they are for windows. And so far the information I have found is for windows. I currently have Ubuntu 13.04 Raring tail. I am using qgis 1.8. I ...
4
votes
0answers
167 views

How to write an address search plugin?

I am migrating some users from MapInfo to QGIS, and before they sign off on it, they want a very simple address search in the same way that we currently have one working in MapBasic. I;ve been having ...
4
votes
0answers
212 views

Display a color ramp legend (of a vector layer) in the qgis map composer

I would like to have a color ramp instead of 10 categories of color when displaying my vector layer in the map composer of QGIS. Is it possible ? Thank you in advance
4
votes
0answers
353 views

How to automatically format the legend labels? in QGIS

I have to do 10 maps (for a start) with "style" -> "graduate" with quantile mode. I need to format the label of the different ranges so that the legend looks comprehensible: Instead of having 1.0000 ...
4
votes
0answers
303 views

What to do about Geoserver WPS Warning “Could not get a ServiceInfo”?

This is the warning i am getting when i try to use this WPS service from QGIS, and the processing take a long time, but doesn't terminate, what might be the problem? 17 Oct 12:33:25 INFO ...
4
votes
0answers
905 views

How to create point labels from midpoints of road polylines in QGIS?

Heres what i want to achieve: i have a roading polyline layer (singlepart ie has several features per road, grouped by an id field), and i want to (after merging the parts) find the mid point of the ...
3
votes
0answers
11 views

QGIS 2.6.1 Complex polygon not displayed properly

I append two images of the same shape file which contains a single polygon with several "lakes". In SAGA it displays correctly with all the lakes as transparent but in QGIS the larger lakes contain ...
3
votes
0answers
24 views

How to display features only if labels are displayed?

In my maps there are several point layers, and each layer has a different labelling rule and priority. Sometime the point density is too high and the labelling engine is not displaying some labels, ...
3
votes
0answers
32 views

QGIS algorithms do not work on copies of shapefiles?

I'm using QGIS 2.6.0. I'm trying to run various algorithms such as "SAGA/Shapes-points/remove duplicates" & "SAGA/Shapes-Grid/Add grid values to points" through the sextant toolbox. When I run ...
3
votes
0answers
50 views

How to calculate areas in raster files

I got three files. The first is a shape file for country boundaries and the second and third are two raster files with the global land covers for 2005 and 2009. I'm thus encharged to calculate the ...
3
votes
0answers
48 views

PyQGIS: Trying to export layer to shapefile

I´m using python in QGIS 2.2 and struggling with an error trying this: # create layer from text _vlayer = QgsVectorLayer(_ur1, "raw", "delimitedtext") works fine but: # export layer to shape ...
3
votes
0answers
50 views

Merge Raster Layer Specific Order in Graphic Modeler

I'm using the Graphic Modeler/Processing Modeler to automate a process. The last step in this process is Merging three different Raster Layers. I'm using the "Merge Raster Layers" from Saga 2.0.8. ...
3
votes
0answers
40 views

Frontal Detection of sst & Chlorophyll image

I am working on sea surface temperature satellite images and looking for delineating gradients in open source on the basis of temperature. Is there any tool like Cayula and Cornillon front detection ...
3
votes
0answers
54 views

QGIS Standalone C++ Application with Qt: “The program has unexpectedly finished”

I'm trying to develop an Standalone Application with Qt and QGIS API. There are several code examples that should work, but they don't. The Problem is that everytime I use "QgsApplication" the ...
3
votes
0answers
53 views

What causes OTB pansharpening ERROR Inputs do not occupy the same physical space?

When I try to use the OTB pansharpening tool an error comes up and I don not really know what the problem is. I have a RGB and a Band8 map (both from Landsat8) which I want to use for the tool. All ...
3
votes
0answers
79 views

Preserve datatypes when using SQLite and QGIS

Following Nathan's SpatiaLite/DBManager solution in this answer, I find that once the layer is loaded from DB Manager into QGIS (2.6.1), any calculated fields are appearing as text values instead of ...
3
votes
0answers
55 views

Correct georeferenced LiDAR data

Often I obtain LIDAR data for concept studies and conventional survey (in dxf format) over a small portion of this. The LIDAR typically covers the broader area and is used for broader studies, ...
3
votes
0answers
65 views

Why do each of my buffer-polygons have different areas

I`m using Qgis 2.2 and 2.4 and loaded a wms-map using the coordinate system ERTS89 UTM 32N. I set 8 points (all in on shp-fileand in UTM 32N) on various locations on the map. After that i created a ...
3
votes
0answers
101 views

QGIS 2.6 Brighton - Graduated Symbols

I can't get graduated symbols to show in QGIS 2.6. This is what I have done. I have two fields of type integer, saved as a shape file which I have tried to import as a shape file and as a secondary ...
3
votes
0answers
19 views

QGIS isn't displaying dates in the attribute table

I have a QGIS project that links to data in a Postgres database. For some reason, QGIS is not displaying any data in date fields. The date fields appear to be fine in Postgres and I have performed ...
3
votes
0answers
115 views

Is there any reason not to upgrade to Windows 8.1?

I have the option to upgrade to 8.1, but before I do I want to see if anyone has had any compatibility issues. I mainly run ESRI, but occasionally use QGIS, and other open source products. Has anyone ...
3
votes
0answers
41 views

How to export two related layers to KML with multigeometry using QGIS?

From QGIS, I would like to create a KML file, for GoogleEarth, which contains multigeometry in that KML file. By example: consider two layers in QGIS -- the first layer contains polygons, and the ...
3
votes
0answers
26 views

QGIS Cross Section Profile Distance using Ellipsoid?

I am working with QGIS 1.8 and 2.6 and can't get any of the Cross Section Profile tools to provide the ellipsoid ("proper") distances. All the distances use geographic coordinates which are too ...
3
votes
0answers
15 views

Action: Move pointfeature to other layer - Point becomes Multipoint

I'm trying to write an action that moves a pointfeature from one layer to another. It works fine until i try to save the layer with the new feature on. He says he can't save a MULTIPOINT to a ...
3
votes
0answers
36 views

Editing Cursor for GPS live tracking in QGIS 2.4

I am interested in using QGIS 2.4 for vessel navigation due to its ability to display NOAA vector charts or BSB's as well as user created shapefiles. I currently oversee a project that requires ...
3
votes
0answers
26 views

Generate a series of ellipses on a line

I am trying to create a series of ellipses (mocked up in green below) of defined dimensions along a line. I have got as far as generating regularly spaced points along the line that are attributed ...
3
votes
0answers
34 views

What Does the Cell Value in a Composite Raster Mean?

When I make a composite raster in QGIS using the GRASS r.composite tool and then click on a certain cell I get these values in the blue/green/red/composite rasters: blue = 124 green = 124 red = 172 ...
3
votes
0answers
71 views

Issue with dissolving a polygons layer in QGIS 2.4

I downloaded a dataset of roads and parks from OSM. I then buffered the roads and merged with the parks. Now - all i want is to dissolve / union all the features in the merged layer. I fail to do it ...