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

learn more… | top users | synonyms (1)

7
votes
0answers
100 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 ...
5
votes
0answers
103 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 ...
5
votes
0answers
212 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
74 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 ...
5
votes
0answers
625 views

Connecting ArcSDE to Quantum GIS for dummies?

I really have a need to be able to connect to and edit ArcSDE data in Quantum GIS. This question has been asked before and apparently is possible, but the instructions are just not specific enough ...
5
votes
0answers
313 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 ...
5
votes
0answers
150 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
185 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
452 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
454 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
645 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
84 views

Connecting Problem: ODBC versus ESRI Personal Geodatabase (*.mdb)

I try over 2 days to connect an ESRI Personal Geodatabase with QGIS 2.8.1 Here is my testing report. Testing environment: Windows 7 64-bit; MS Office 32-bit; QGIS 32-Bit 1. Step: Creating an ...
4
votes
0answers
73 views

QGIS and the South Pole: bug or feature?

I am trying to work with some data from Antarctica in QGIS. I have defined this new projection: +proj=laea +lat_0=-90 +lon_0=0 +datum=WGS84 +units=m +no_defs And started adding a few vector layers. ...
4
votes
0answers
134 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
65 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
142 views

Is there a “Disperse Markers” tool for QGIS?

I am using ArcGIS, but either I would like to use QGIS and maybe want to switch completely later. A have a point overlapping problem, as a result of geocoding of addresses. I have not found any ...
4
votes
0answers
54 views

How to setup default toolbars and menu item?

I need to customize the UI for a group of users at another office. I want to turn off a bunch of toolbars and menus that are not needed. I know how to save my configurations (Settings -> ...
4
votes
0answers
176 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
208 views

How to create a chart of the altitude of points?

I am using shapefiles with basic informations including the x-, y- and z-coordinates. I want to see how the objects (in this case points, which are finds from an excavation) are scattered along the ...
4
votes
0answers
336 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
371 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
210 views

QGIS does not read ESRI Geodatabase correctly

I have a geodatabase from the EPA that does not seem to me reading correctly with Quantum GIS. QGIS Version 1.8.0 (Lisboa) and GDAL/OGR 1.9.2 When I open the attribute table the first two columns ...
4
votes
0answers
104 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
199 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
225 views

Can you set a QGIS print composer to render the map as default?

I have set up a number of templates for the print composer in QGIS. In the Print Composer, there is the option to have the map image displayed in 3 ways: as a blank rectangle with no updates until ...
4
votes
0answers
246 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
580 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
365 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
441 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
959 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
35 views

How to develop QGIS Plugin to fully run Spatial Queries With PostGIS?

I'm developing a QGIS plugin that fully run spatial queries with PostGIS. Actually I developed all spatial queries wish need some adjustment. I'm looking for some ressources or documents to know how ...
3
votes
0answers
67 views

Which projection can I use to see alignments on great circles?

I want to put on a QGIS map some historical sites to check if they are aligned. If an alignement exists, the points should stay on a great circle (is this correct?). I want to visually verify this ...
3
votes
0answers
32 views

Output formats for QGIS Heatmap plugin not appearing in drop-drown in Ubuntu

I've been trying to use the heatmap plugin on QGIS (2.8.2) on Ubuntu(14.04) but the drop down for the output formats doesn't get populated. Selecting the drop-down allows me to press OK on the plugin ...
3
votes
0answers
21 views

Programatically export map clusters in QGIS

I'm trying to export each microcluster of a large map into a composed map that shows the ff on an A4 sheet: 1) Cluster/grid box of the map 2) Larger index map with the pertinent region highlighted ...
3
votes
0answers
101 views

Is it possible to create Isochrones in QGIS GUI?

I'm new to QGIS and have tried to create isochrones around points for quite some time. Is there any option to create isochrones on the GUI in QGIS? I know how to create them using pgAdmin (using eg ...
3
votes
0answers
51 views

How to offset polyline geometries (not symbology) using QGIS?

I have a polyline layer which has a road network digitized, up the center, in both directions however the polyline are sat "one on top of the other". I can display the lines separately by ...
3
votes
0answers
57 views

How to make a virtual field function use the same Ellipsoid settings as the normal field calculator?

I have a new shapefile layer in CRS 3857, in a project that has the same CRS. Under project properties, the measure tool is on ellipsoid WGS 84. When i use the field calculator to create a new field ...
3
votes
0answers
92 views

Performance difference between focal statistics (ArcGIS) and neighbor (GRAS or QGIS)

I tested minimum, maximum, and average neighbor (circle radius = 161 pixel) using ArcGIS, GRASS and QGIS: ArcGIS (10.1): it takes only one minute GRASS (6.4.3): it takes 123 minutes for every output ...
3
votes
0answers
83 views

QGIS 2.8 PrintComposer, no coordinates shown

I tested under MacOS 10.10.3 and 10.9.5 now: In the QGIS v2.8 Print Composer I don´t get coordinates shown when I want to create a map sheet and activate "Draw coordinates". I can do all settings ...
3
votes
0answers
31 views

Saving a calibrated route in QGIS for “future” use

Can a Calibrated Vector (after using LRS) be saved with M values, so that the file does not have to be calibrated every time is used? We're currently working on State road data, and it has many ...
3
votes
0answers
106 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
35 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
65 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
306 views

Connect to QGIS 2.6 Python Plugin function via button on custom feature form

I am trying to connect to a QGIS 2.6 Python plugin function via a custom feature form button. On my feature form, I'm attempting to do a few things : enable the updateButton only if the ...
3
votes
0answers
100 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
59 views

Create buffer based on polyline without line end caps and without dissolving the created polygons in QGis

I have a projected line layer (Shapefile) in QGIS. For every line segment I want to create a polygon without line end caps. The resulting polygone should not be dissolved to a single one. I tried ...
3
votes
0answers
186 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
86 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
67 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
468 views

How to install QGIS with ECW support on Mac?

I bought a imac recently and I tried to install qgis: without success! It is not possible to read the raster files. I installed GDAL ECW plugin, but it is necessary to copy and paste another file ...