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

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9
votes
0answers
787 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
71 views

Is it possible to generate a boustrophedon pattern which fill a vector Region with GRASS?

Every thing is in the title... I have a vector region in GRASS. And I would like to generate a vector (a polyline) beeing the bostrophedon pattern which fill this region. In the picture bellow, I ...
6
votes
0answers
214 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 ...
6
votes
0answers
527 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
51 views

Getting weird lines in Print Composer QGIS

I am working with QGis 2.8 and want to use the print composer to create a jpg image. I used this PlugIn (https://github.com/jdugge/ClipToHemisphere) to create the globe. The graticules I created the ...
5
votes
0answers
144 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
114 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 ...
5
votes
0answers
156 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
408 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
411 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
624 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
73 views

MapInfo “Boundary Select”, “Sum Attributes”, and “Update Column by Spatial Query” in QGIS?

I´m a MapInfo user, I´ve gone over to QGIS and it´s got a lot going for it, except for some "missing" simple features from MapInfo I just can´t do without.... MapInfo Boundary Select - spatial query ...
4
votes
0answers
92 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 ...
4
votes
0answers
84 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
45 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 ...
4
votes
0answers
66 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
239 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
164 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
289 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
319 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
352 views

QGis Save Raster as Rendered Image

In QGIS 1.9.0 Master, when you right click on a raster in the Layers Panel and select "Save As", you can select the output mode to be "Raw Data" or "Renedered Image". When selecting the Rendered ...
4
votes
0answers
88 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
181 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
228 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
419 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
324 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
425 views

How to reverse-georeference with QGIS?

I have a map with a "strange" projection (it's basically hand-painted, not an exact one). I can easily georeference it in QGIS using the Georeferencer plugin and the Thin Plate Spline transformation ...
4
votes
0answers
923 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
75 views

Why does field calculator compute area in square meters?

I am using EPSG:102748, and have set my Settings/Option preferred measurement units to ft. My CRS is NAD_1983_StatePlane_Washington_North_FIPS_4601_Feet, and when I use the measure tool, it returns ...
3
votes
0answers
31 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
57 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
78 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
121 views

SAGA is not working within sextante (QGIS processing installed in Ubuntu)

Recently i decided to start working in Ubuntu (version 14.04). My first step was to add the ubuntugis-unestable repository, and then proceed to install SAGA, GRASS, OTB, QGIS and the bindings between ...
3
votes
0answers
67 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
53 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
90 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
70 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
192 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
22 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
167 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
55 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
34 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
18 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
45 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
32 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
97 views

Does QGIS work with Anaconda?

I am trying to get QGIS to work with the Anaconda distribution of Python but I do not know how to get this to work. In one of the answers it was mentioned that QGIS does not work with Anaconda and I ...
3
votes
0answers
79 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 ...
3
votes
0answers
96 views

How to snap and move circles by the center?

I have a point layer, and a polygon layer with buffers of a given radius around each point. I need to move points, and check that each buffer is not above forbidden land/plots. In autocad, you can ...
3
votes
0answers
123 views

Batch export to shapefile by attribute field in QGIS

I have a project in QGIS where I am creating a map of plants over a large area. I want to take the "Genus" field (of which there are 100 hundred values) and essentially create 100 shapefiles based on ...
3
votes
0answers
61 views

Resampling air temperature gridded data to sub-grid resolution

I'd like to obtain a 30-m resolution gridded dataset of air temperature from the ~1km gridded data of WorldClim, of Hijmans et al., 2005) for a mountainous region. The easiest procedure (I thought ...